US007525717B2

(12) United States Patent (10) Patent No.: US 7,525,717 B2 Byker et al. (45) Date of Patent: Apr. 28, 2009

(54) MULTI-LAYER LIGAND EXCHANGE (56) References Cited THERMOCHROMC SYSTEMS U.S. PATENT DOCUMENTS (75) Inventors: Harlan J. Byker, West Olive, MI (US); 2,710,274 A 6, 1955 Kuehl Frederick A. Millett, Grand Haven, MI (Continued) (US); Paul H. Ogburn, Jr., Hudsonville, FOREIGN PATENT DOCUMENTS MI (US); Douglas A. Vander Griend, Grand Rapids, MI (US); Brad S. EP 0356116 2, 1990 Veldkamp, Zeeland, MI (US); Derick D. (Continued) Winkle, Holland, MI (US) OTHER PUBLICATIONS Kirk-Othmer Encyclopedia of Chemical Technology. Third Edition, (73) Assignee: Pleotint, L.L.C., West Olive, MI (US) vol. 6, "Chromogenic Materials (Electro-. Thermo-) Electrochromic (*) Notice: Subject to any disclaimer, the term of this and Thermochromic,” pp. 129-142, John Wiley & Sons (1979). patent is extended or adjusted under 35 (Continued) U.S.C. 154(b) by 0 days. Primary Examiner David N Spector (74) Attorney, Agent, or Firm Thompson Hine LLP (21) Appl. No.: 11/849,659 (57) ABSTRACT (22) Filed: Sep. 4, 2007 Ligand exchange of thermochromic, LETC, systems exhib (65) Prior Publication Data iting a reversible change in absorbance of electromagnetic radiation as the temperature of the system is reversibly US 2008/O1 OO903 A1 May 1, 2008 changed are described. The described LETC systems include one or more than one transition metalion, which experiences Related U.S. Application Data thermally induced changes in the nature of the complexation (60) Provisional application No. 60/841,827, filed on Sep. or coordination around the transition metal ion(s) and, 1, 2006. thereby, the system changes its ability to absorb electromag netic radiation as the temperature changes. (51) Int. Cl. In accordance with one aspect of the present invention, a GO2F IMOI (2006.01) thermochromic device is disclosed comprising at least two GO2F I/00 (2006.01) thermochromic layers when each thermochromic layer G09G 3/34 (2006.01) includes a polymer, at least one transition metal ion, at least CO7F 15/04 (2006.01) one HeL ligand capable of forming a HeMLC with the tran sition metal ion and at least one LeL ligand capable of form (52) U.S. Cl...... 359/288; 35.9/321; 34.5/106; ing an LeMLC with the transition metal ion. In accordance 54.6/10 with yet another aspect of the present invention, the thermo chromic device further includes a separator between the first (58) Field of Classification Search ...... 250/330; and second thermochromic layers to prevent intermixing of 345/106; 359/288,321; 54.6/10; 556/37 the contents of the layers. See application file for complete search history. 19 Claims, 9 Drawing Sheets

Influence of AS' on Absorbance vs. Temperature 5 AS'=160 AS'=140 4 - AS=180 : 3 - AH = 60 kJ/mole e(LeMLC) = 1 5. g(HMLC) = 280 2 b = 0.075cm MeT = 0.2 HeLT = 1.6 LeLT = 2.5

O O 100 200 300 400 500 600 Temperature (C) US 7,525,717 B2 Page 2

U.S. PATENT DOCUMENTS Srivastava, J. et al., “Synthesis of Polyacrylic Acid Based Thermochromic Polymers.” Proc. of SPIE, vol. 5062, pp. 111-115 3, 192,101 A 6/1965 Koenig (2003). 3,236,651 A 2f1966 Marks et al. Kojima, K. et al., “Pressure and Temperature Effects on Octahedral 3,445,291 A 5, 1969 Stein Tetrahedral Equilibria in Pyridine Solutions of Some Cobalt(II) 3,723,349 A 3, 1973 Heseltine et al. Halides.” Bull. Chem. Soc. Jpn., vol. 56, No. 3, pp. 684-688 (Mar. 3,816,335 A 6, 1974 Evans 1983). 4.575,259 A 3, 1986 Bacci et al. Griffiths, T.R. et al., “Effects of Cations upon Absorption Spectra Part 4,970,315 A 11, 1990 Schmidhalter 4.-Octahedral-Tetrahedral Equilibria between Chloro-nickel(II) 5,159,057 A 10/1992 Perry Complexes in Ethylene Glycol and Glycerol.” Trans. Faraday Soc., 5,240,897 A 8, 1993 Braun et al. 6,084,702 A 7/2000 Byker et al. 65, pp. 3179-3 186 (1969). 6,362,303 B1 3/2002 Byker et al. Griffiths, T.R. et al., “Effects of Cations upon Absorption Spectra Part 6,446,402 B1 9/2002 Byker et al. 2.-Formation of Tetrahedral Tetrachloronickelate(II) in Aqueous 6,620,872 B2 9, 2003 Fisher Solution.” Trans. Faraday Soc., 65, pp. 1727-1733 (1969). 6,665,107 B2 12/2003 Forgette et al. Gill, Naida S. et al., "Complex Halides of the Transition Metals. Part 6,737,159 B2 5, 2004 Garrett et al. I. Tetrahedral Nickel Complexes,” J. Chem. Soc., pp. 3397-4007 6,737.418 B2 5/2004 Hogenkamp et al. (1959). 6,998,072 B2 2/2006 Welch et al. Sunamoto, J. et al., “Solvochromism and Thermochromism of 7,179,535 B2 2, 2007 Fisher Cobalt(II) Complexes Solubilized in Reversed Micelles.” Bulletin of 7,226,966 B2 * 6/2007 Kambe et al...... 524/432 the Chemical Society of Japan, vol. 51, No. 11, pp. 3130-3135 (Nov. 7,256.296 B2 8, 2007 Diamond et al. 1978). 2006, O159874 A1 7/2006 Koran et al. Marinkovic, M. et al., “Thermochromic complex compounds in 2008/0100902 A1* 5/2008 Byker et al...... 359,288 phase change materials: Possible application in an agricultural green 2008/0105851 A1* 5/2008 Byker et al...... 252/408.1 house.” Solar Energy Materials and Solar Cells, 51, pp. 401-411 2008/0106781 A1* 5/2008 Byker et al...... 359,288 (1998). Arutunjan, R.E. et al., “Thermochromic Glazing for Zero Net FOREIGN PATENT DOCUMENTS Energy House.” Glass Processing Days, Conference Proceedings, JP 2004-3596.23 12, 2004 pp. 299-301, Eighth International Conference (Jun. 15-18, 2003). WO WO 2008028128 A1 * 3, 2008 Rozova, K.B. et al., Abstract for "Sun screening thermochromic glazing materials.” TsNIIEP, USSR. Svetotekhnika (1986), (10), OTHER PUBLICATIONS 12-14. CODEN: SVETAGISSN: 0.039-7067. Journal written in Rus International Search Report of the International Searching Authority Sian. CAN 107:30324 AN 1987:43.0324 CAPLUS. regarding International Application No. PCT/US2007/077385 (Feb. Greenberg, C. “Chromogenic Materials (Thermochromic).” Kirk 4, 2008). Othmer Encyclopedia of Chemical Technology 4th Edition, vol. 6,pp. Written Opinion of the International Searching Authority regarding 337-343, John Wiley & Sons. International Application No. PCT/US2007/077385 (Feb. 24, 2008). Sone, K. et al., Inorganic Thermochromism, pp. 1-71, Springer Long, G.J. et al., “Transition Metal Chemistry of Quinuclidinone Verlag (1987). Containing Ligands. III. Electronic and Structural Properties of Sev Angell, C.A., “Octahedral-Tetrahedral Coordination Equilibria of eral Transition Metal Complexes Containing trans-2-(2'- Nickel (II) and Copper (II) in Concentrated Aqueous Electrolyte Quinolyl)methylene-3-quinuclidinone.” Inorganic Chemistry, vol. Solutions,” Journal of the American Chemical Society,88 (22), pp. 13, No. 2, pp. 270-278 (XP-002465696) (1974). 5192-5198 (Nov. 20, 1966). Kuroiwa, K. et al., “Heat-Set Gel-like Networks of Lipophilic Co(II) Day, J.H., “Thermochromism of Inorganic Compounds.” Chemical Triazole Complexes in Organic Media and Their Thermochromic Reviews, vol. 68, No. 6, pp. 649-657 (Nov. 25, 1968). Structural Transitions,” Journal of the American Chemical Society, Scaife, D.E. et al., “Influence of Temperature on Some Octahedral vol. 126, pp. 2016-2021 (XP-002465697) (2004). Tetrahedral Equilibria in Solution.” Inorganic Chemistry, vol. 6, No. Arutunjan, R. et al., “Smart Thermochromic Glazing for Energy Saving Window Applications.” Poster Session Abstract8, The Fourth 2, pp. 358-365 (Feb. 1967). International Conference on Advanced Optical Materials and Sunamoto, J. et al., “Formation of Polynuclear Cupric Halides in Devices, Tartu, Estonia (Jul. 6-9, 2004). Cationic Reversed Micelles.” Inorganic Chemisry, vol. 19, No. 12, Kojima, K. et al., “Pressure and Temperature Effects on Octahedral pp. 3668-3673 (1980). Tetrahedral Equilibria in Pyridine Solutions of Some Cobalt(II) Sunamoto, J. et al., “Reversed Micelles to Mimic the Active Site of Halides. II.” Bull. Chem. Soc. Jpn. vol. 57, No. 3, pp. 879-880 (Mar. Metalloenzymes.” Inorganica Chimica Acta, 92, pp. 159-163 (1984). 1984). Katzin, L.I., “Energy Value of the Octahedral-Tetrahedral Coordina Yanush, O.V. et al., “Laminated Glass with Variable Transmission for tion Change.” The Journal of Chemical Physics, vol. 35. No. 2, pp. Daylight Regulation.” Glass Processing Days, Conference Proceed 467-472 (Aug. 1961). ings, pp. 815-817. Seventh International Conference (Jun. 18-21. Sestili, L. et al., “Formation Equilibria of Pseudotetrahedral Co (II) 2001). Halogenocomplexes in Acetonitrile.” J. Inorg. Nucl. Chem. No. 32. Halopenen, I. et al., “Smart Laminated Glasses for Regulation of pp. 1997-2008 (1970). Lighting.” Glass Processing Days, Conference Proceedings, pp. 324 326, Sixth International Conference (Jun. 13-16, 1999). * cited by examiner U.S. Patent Apr. 28, 2009 Sheet 1 of 9 US 7,525,717 B2

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Figure 46 U.S. Patent Apr. 28, 2009 Sheet 7 Of 9 US 7,525,717 B2

Figure 47. Ratio of Keg(85C) to Keg (25C) as a Function of AH' 450 400 3 350 l S 300 g a 250 s a 200 l 3 150 g NM 100 50 O 40 50 60 70 80 90 AH' (kJ/mole)

Figure 48. Influence of AS' on 5 Absorbance Vs. Temperature

AS'=160 AS'=140 4 - O AS=180

3 - AH = 60 kJ/mole a c(LeMLC) = 1 2 s(HeMLC) = 280 2 2 - b = 0.075cm MeT = 0.2 1 - HeLT = 1.6 LeLT = 2 O O 100 200 300 400 500 600 Temperature (C) U.S. Patent Apr. 28, 2009 Sheet 8 of 9 US 7,525,717 B2

Figure 49. Temperature Dependence of Absorbance for Various Ratios, R., of HaLT/MT

R=2, Le L=0.57M 3, Le L=0.66M 4, LeL=0.77M 4, LeL=0.77M 5,, L&L=0.89M 8,, LeL=1.30M

25 35 45 55 65 75 85 Temperature (C)

Figure 50. Transmission of SRT"Vertically Positioned

Windows Based on Time of Day and Direction

8:00 9:00 10:00 11:00 12:00 100 2:00 3:OO 4:00 5:00 6:00 7:00 8:00 9:00 AM AM AM AM PM PM PM PM PM PM PM PM PM PM Time of Day U.S. Patent Apr. 28, 2009 Sheet 9 Of 9 US 7,525,717 B2

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Figure 56

Figure 58

900 US 7,525,717 B2 1. 2 MULTI-LAYER LIGAND EXCHANGE BACKGROUND THERMOCHROMC SYSTEMS Many chromogenic phenomena are known in which a CROSS REFERENCE TO RELATED change in color or a change in light absorption results from APPLICATION Some action or stimulus exerted on a system. The most com mon chromogenic phenomena are electrochromics, (EC), This application claims the benefit of U.S. Provisional photochromics, (PC), and thermochromics, (TC). Many phe Application Ser. No. 60/841,827 filed on Sep. 1, 2006, the nomena are also known in which optical changes, like light contents of which are hereby incorporated by reference. scattering or diffuse reflection changes, take place as a result DEFINITION OF TERMSFABBREVIATIONS 10 of Some action or stimulus exerted on a system. Unfortu nately, referring to these as chromic phenomena has led to a (4-MeOPh)PO-bis(4-methoxyphenyl)phosphinate fair amount of confusion in the past. We prefer to distinguish 18-crown-6=1,4,7,10,13,16-hexaoxacyclooctadecane light scattering systems from chromogenic systems by refer 1-EtBIMZ=1-ethyl-1H-benzimidazole ring to the light scattering phenomena as a phototropic, ther 1-MeBIMZ=1-methyl-1H-benzimidazole 15 motropic or electrotropic phenomena. This distinction and 4-(3-PhPr)Pyr-4-(3-phenylpropyl)pyridine) other distinctions are elaborated on below. acac-acetylacetonate In general, and especially for the sake of the patent appli BIMZ=benzimidazole cation, the terms used for an optical phenomena, should relate BusPO-tributylphosphine oxide to the direct, primary action causing the phenomena. For CFCOOLi=lithium trifluoroacetate example, modern day electrochromic systems generally Di-TMOLP-di-trimethylolpropane involve electrochemical oxidation and reduction reactions. DMSO-dimethylsulphoxide Thus an electrical process directly causes materials to change DP-dipyridyl-2,2'-bipyridine their light absorbing or light reflecting properties. Alterna EG-ethylene glycol tively, electrical energy can also be used to generate heat or EXM=Exchange Metal 25 light and this heat or light, in turn, may be used to affect a HeL high molar absorption coefficient ligand high epsilon thermochromic or a photochromic change. However, the indi ligand rect use of electricity should not make these electrochromic HeMLC-high molar absorption coefficient MLC-high epsi phenomena. For example, a thermochromic layer may lon MLC increase in temperature and light absorption when in contact LETC-ligand exchange thermochromic(s) 30 with a transparent conductive layer which is resistively heated LeL-low molar absorption coefficient ligand-low epsilon by passing electricity through the transparent conductive ligand layer. However, in accordance with the terminology used LeMLC-low molar absorption coefficient MLC-low epsilon herein, this is still athermochromic device and should not be MLC called an electrochromic device. Also, just because an electric m-molal-moles of solute per kilogram of solvent 35 light produced UV radiation that caused a color change by a M-molar-moles of solute per liter of solution photochemical reaction, like the ring opening of a spiroox Me-metalion azine compound, that would not make Such a procedure a MLC-metal-ligand complex demonstration of electrochromics. N-Bu-di(1-MeBIMZ-2-yl-methyl)amine-N,N-bis(1-me A similar distinction should be made with a thermochro thyl-1H-benzimidazol-2-yl)methylbutanamine 40 mic layer that is responsive to Sunlight as described in U.S. NIR=near infrared Pat. Nos. 6,084,702 and 6,446,402. The thermochromic layer nm nanometer may be heated by absorbing Sunlight or being in contact with NPG-neopentylglycol=2,2-dimethylpropane-1,3-diol another layer that absorbs Sunlight. Here Sunlight exposure N-Pr-dipicolylamine-N,N-bis(pyridine-2-ylmethyl)propan changes the color and/or the amount of light absorbed by the 1-amine 45 thermochromic layer. However, this is still a thermochromic N—Pr-DPamine-N-propyl-N-pyridin-2-ylpyridin-2-amine phenomenon because a heat induced temperature change PhP=PPh=triphenylphosphine causes the chromogenic change and the same change takes PVB poly(vinyl butyral) place when the layer is heated by other means. The absorbed R/O-Ring Opening TC Compound photons from the Sun are only converted to heat and do not 50 directly cause a photochromic change. Accordingly, the term SRTTM=Sunlight responsive thermochromic photochromics should be reserved for systems in which the TBABr-tetrabutylammonium bromide absorption of a photon directly causes a photochemical or TBACl-tetrabutylammonium chloride photophysical reaction which gives a change in color or a TBAI-tetrabutylammonium iodide change in the system's ability to absorb other photons. TC-thermochromic(s) 55 In addition to chromogenic systems, there are a variety of TEAC1.HO-tetraethylammonium chloride monohydrate systems with reversible changes in light scattering. The more TMEDA=NN,N',N'-tetramethylethylenediamine widely studied light scattering systems include: (1) lower TMOLP-trimethylolpropane=2-ethyl-2-(hydroxymethyl) critical solution temperature, LCST, polymeric systems; (2) propane-1,3-diol polymer dispersed liquid crystal, PDLC, systems; (3) poly TTCTD=14.8, 11-tetrathiacyclotetradecane 60 mer stabilizer cholesteric texture, PSCT systems and (4) UV=ultraviolet thermoscattering, TS, systems. Additional description of Y=% white light transmission based on 2 exposure of a Des these and other light scattering phenomena may be found in light source U.S. Pat. No. 6,362,303. In the past, several of these phenom e-molar absorption coefficient molar absorptivity, in liters/ ena have been called thermochromic and even electrochro (molecm) 65 mic. From our standpoint these phenomena are neither ther Y-BL gamma-butyrolactone mochromic nor electrochromic since the word chroma relates w wavelength in nanometers to color and the intensity and quality of color. These are better US 7,525,717 B2 3 4 termed thermotropic or electrotropic to help indicate the results in a reversible change in absorbance of electromag change in state that takes place. netic radiation as the temperature of the system is reversibly Definitions rarely cover every eventuality, especially when changed. That the change is reversible means that the amount it comes to borderline cases. Hence electrochemical systems of change in absorbance remains fairly consistent, for both that change from colorless and non-light scattering to specu the increase and decrease in absorbance throughout a given larly reflecting are still generally termed electrochromic temperature range, on repeated temperature cycling, for some because of the electrochemical nature of these processes. useful number of cycles. The thermochromic systems of this Also, some thermochromic systems involve changes between invention have a reversible, net increase in their ability to liquid and solid phases and could conceivably be called ther absorb light energy in the visible and/or NIR range as the motropic systems. But these systems have dramatic changes 10 temperature of the system is increased and a net decrease in in light absorption and are still termed thermochromic. On the their ability to absorb light energy in the visible and/or NIR other side, Some reversible light scattering systems may have range as the temperature of the system decreases for tempera Some spectral selectivity to the light scattering and hence give tures within the active range of the system. The active tem rise to some color appearance. Yet the primary change is perature range of the system is determined by the thermody between light scattering and non-light scattering States. Even 15 namic properties of the LETC reactions. For many of our the change in some systems from colorless and non-light applications the active temperature range includes 0 to 100 scattering to a frosted, diffusely reflecting and white appear degrees Celsius. ance might Suggest a color change to the color white. How LETC systems comprise one or more than one transition ever, we still term these tropic and not chromic changes. metal ion, which experiences thermally induced changes in In Summary, systems without any substantial change in the nature of the complexation or coordination around the light scattering, that primarily involve a change in color, transition metal ion(s) and thereby the system changes its intensity of color or absorption of light, as well as those ability to absorb electromagnetic radiation as the temperature electrochemical and thermochemical phenomena that give a changes. change in specular reflectance, are herein understood to be In accordance with particularly useful systems described chromic or chromogenic phenomena. One of these chromic 25 herein, the electromagnetic radiation, for which absorbance phenomena—thermochromics, as defined herein, is the Sub changes occur, is in the visible and NIR portions of the elec ject of the present invention. tromagnetic spectrum. Some of the systems described herein Many thermochromic materials and phenomena are also exhibit changes in absorbance in the ultraviolet. The known. These include reversible and irreversible changes in change in light absorption on heating of the LETC systems optical character. A well known thermochromic phenomena, 30 generally results in a change from one color to another color for use with windows, involves metal oxide thin films. Most and/or a darkening of the color of the system. However, if the notably films of VO, and doped versions thereof, are known increase in light absorption is predominantly in the NIR, the to reversibly change their specular reflectance in the NIR with LETC system may still be very useful even though little or no changes in temperature. Thermochromic processes with visual color change occurs. changes in light absorption are observed when heating 35 The term visible light generally applies to that portion of causes: (1) an increase in the amount of ring opening of the electromagnetic spectrum sensed by the human eye. certain spiro compounds; (2) the dissociation of certain While some definitions might limit the terms “light' and/or anions from certain triarylmethane dyes or (3) the dissocia “photon’ to the visible portion of a spectrum produced by a tion of certain “dimeric' substances into highly absorbing Source of electromagnetic radiation, for the purposes of this “monomeric' free radicals. Thermochromic phenomena are 40 patent application, the terms "light' and “photon’ also apply also involved in phase change systems which change from to the near ultraviolet and near infrared portions of the spec highly absorbing to colorless or nearly colorless when certain tra, incident on the earth’s Surface, from sources of electro pH indicators change their association with certain weak magnetic radiation like the Sun. The wavelengths of ultravio acids during a melting or Solidification process. let light of interest are from about 280 nanometers to about Still other reversible thermochromic systems involve ther 45 400 nanometers. The wavelengths of the visible light of inter mally induced changes in the way ligands associate with est are from about 400 nanometers to about 700 nanometers. transition metal ions. The present application discloses par The wavelengths of NIR light of interest for our LETC sys ticularly useful versions of these metal-ligand thermochro tems are from about 700 nanometers to about 1400 nanom mic systems and combinations of these systems with other eters. Thus the visible through NIR range wherein reversible thermochromic systems. 50 net light energy absorbance increases are of interest is from about 400 nm to about 1400 nm. SUMMARY The energy of each photon is inversely proportional to its wavelength and is determined by Planck's constant multi In accordance with one aspect of the present invention, a plied by the frequency of that photon. As a LETC system is thermochromic device is disclosed comprising at least two 55 heated, at least one light absorbing species decreases in con thermochromic layers when each thermochromic layer centration thereby decreasing the systems ability to absorb includes a polymer, at least one transition metal ion, at least photons related to its absorption spectra. At the same time, at one HeL ligand capable of forming a HeMLC with the tran least one light absorbing species increases in concentration sition metalion and at least one LeL ligand capable of form thereby increasing the systems ability to absorb photons ing an LeMLC with the transition metal ion. In accordance 60 related to its absorption spectra. The ratio of the amount of with yet another aspect of the present invention, the thermo energy absorbed to the amount incident on the system chromic device further includes a separator between the first depends on several factors including (1) the absorption spec and second thermochromic layers to prevent intermixing of tra of the LETC system at a given temperature; (2) the inten the contents of the layers. sity and spectral distribution of the light source and (3) the The thermochromic systems of the present application are, 65 exposure time. herein, termed: ligand exchange thermochromic, LETC, Sys For certain LETC systems disclosed and for the particular tems. LETC systems have thermochromic activity which applications thereof, as the temperature of the LETC system US 7,525,717 B2 5 6 increases there is an increase in the ratio of the total energy There is extensive literature on MLC's apart from TC per unit time of all visible and NIR electromagnetic radiation, technology; see for example: (photons), absorbed by the system to the total energy per “Inorganic Electronic Spectroscopy’ by A. B. P. Lever, unit time of all visible and NIR electromagnetic radiation, Elsevier Publishing Co. (1968) and (1984). (photons), incident on the system from a broadband Source “Comprehensive Coordination Chemistry: Synthesis, Reac of electromagnetic radiation incident on the system. For par tions, Properties & Applications of Coordination Com ticularly useful applications of the LETC systems or layers pounds' Editors R. D. Gillard and G. Wilkinson, Elsevier disclosed herein, there is a net increase in the ability of the Ltd. (1987) system to absorb incident visible and NIR sunlight power, (or “Comprehensive Coordination Chemistry II From Biology to energy over time), as the temperature of the system increases. 10 Nanotechnology”. Editors J. A. McClevety and T. A In most cases, this means that the LETC systems become Meyer, Elsevier Ltd. (2004) darker in color as the temperature of the systems increase. The LETC systems may be liquid solutions, solid polymer BRIEF DESCRIPTION OF FIGURES layers, or semi-solid polymer layers, physical gels or chemi cal gels. 15 FIG. 1-46 are absorption spectra for the systems described The present application discloses LETC systems, ligands, in Examples 1-46, respectively; particularly useful compositions and combinations of LETC FIG. 47 is a plot of K (85C) to K, (25C) as a function of systems. AH; The present application describes high performance TC FIG. 48 shows the influence of AS' on Absorbance and systems based on iron, cobalt, nickel and copper ions with a Temperature; variety of ligands. FIG. 49 shows the temperature dependence of Absorbance The present application describes LETC systems with for various ratios of HeL/IM: advantageous ratios of ligand to metalion concentrations and FIG. 50 is a plot of Transmission of SRTTM vertically particularly useful systems with respect to the choice of sol positioned windows based on time of day and direction; vent and/or polymer matrix. 25 FIG. 51-57 are absorption spectra for the systems The present application discloses high performance TC described in Examples 279-285, respectively; and systems in combination with a seal which minimizes the FIG. 58 is the spectral data for Example 294. ingress of oxygen. LETC systems by themselves and in combination with DETAILED DESCRIPTION other thermochromic systems and compositions are dis 30 closed. The term “substituted as in “substituted alkyl and the Also described herein are processes for producing thermo like, means that in the group in question, at least one hydrogen chromic layers and novel structures for the use of LETC atom bound to a carbon atom is replaced with one or more systems in various applications. Substituent groups, such as hydroxy, alkoxy, alkylthio, phos Described herein are applications of LETC systems in 35 phino, amino, halo, silyl, and the like. When the term “sub variable light transmission windows for residential and com stituted introduces a list of possible substituted groups, it is mercial buildings including skylights and atrium glazing and intended that the terms apply to every member of that group. variable light absorption windows for boats, ships, aircraft The term “alkyl as used herein refers to a branched or and motor vehicles including moon roofs and Sun roofs. The unbranched Saturated hydrocarbon group typically although windows may include artful designs of different colored 40 not necessarily containing 1 to about 20 carbon atoms, more LETC systems like a variable light transmission stained glass particularly containing 1 to about 6 carbon atoms. The term window. “arylas used herein refers to a group containing an aromatic The systems disclosed herein are particularly useful in ring. Aryl groups herein include groups containing a single providing the thermochromic activity in the inventions dis aromatic ring or multiple aromatic rings that are fused closed in U.S. Pat. Nos. 6,084,702 and 6,446,402, the con 45 together, linked covalently, or linked to a common group Such tents of which are hereby incorporated by reference. as a methylene or ethylene moiety. In particular embodi ments, aryl substitutents include 6 to about 50 atoms other TC Systems and MLC Systems than hydrogen, typically 6 to about 20 atoms other than hydrogen. Furthermore, the term “aralkyl refers to an alkyl Thermochromic systems that involve reversible changes in 50 group Substituted with an aryl group typically containing the association of ligands with transition metals have been from 7 to 20 carbon atoms. described previously. Many of these, along with other types The terms "heterocycle' and "heterocyclic” refer to a of inorganic thermochromic materials, are described in “Inor cyclic group, including ring-fused systems, including het ganic Thermochromism' by K. Sone and Y. Fukuda, eroaryl groups as defined below, in which one or more carbon Springer-Verlag (1987) and the references therein. 55 atoms in a ring is replaced with a heteroatom-that is, anatom Other literature that describes thermochromics involving other than carbon, such as nitrogen, oxygen, Sulfur, phospho transition metal ions is found in: rus, boron or silicon. Heterocycles and heterocyclic groups Jesse Day, “Chromogenic Materials, Electrochromic and include Saturated and unsaturated moieties, including het Thermochromic’ in Kirk-Othmer Encyclopedia of Chemi eroaryl groups as defined below. The term "heteroaryl” refers cal Technology 3" Edition Volume 6, pp 129-142, John 60 to an aryl group that includes one or more heteroatoms in the Wiley and Sons (1979). aromatic ring. Charles Greenberg, “Chromogenic Materials (Thermochro LETC activity is observed when a temperature change mic) Kirk-Othmer Encyclopedia of Chemical Technol causes the association of ligands with transition metal ions to ogy 4' Edition Volume 6, pp. 337-343, John Wiley and change or exchange in Such a way that a variation in the UV, Sons. 65 visible and/or the NIR light absorption of the system occurs “Thermochromism of Inorganic Compounds”. J. H. Day, giving a reversible net increase in the systems ability to Chemical Reviews 68,649-657 (1968) absorb visible and/or NIR light energy as the temperature is US 7,525,717 B2 7 8 increased. A LETC system includes, at least, one type of ligand appears in the main or predominant equilibrium reac transition metal ion and at least two types of ligands. Unless tion equation of the LETC system. A ligand, not coordinated the ligands function as the entire solvent, the system also to a metalion, that appears on the same side of an equilibrium includes some other type of solvent for the transition metal equation as the LeMLC(s) is a HeL. A ligand, not coordinated ion and the ligands so that they are together in a liquid or a to a metalion, that appears on the same side of an equilibrium Solid solution. equation as the HeMLC(s) is a LeL. This is illustrated by the The solvent may be an aqueous, nonaqueous or ionic liq following equation: uid; a plasticizer, a polymer; some additive(s) dissolved in a LeMLC+y HeL HeMLC+xLeL (1) polymer; the matrix portion or phase of an organic, inorganic or hybridgel; the liquid portion or phase of a gel; or some 10 wherein X and y are numeric variables that designate the combination of these acting as co-solvents. The solution may number of LeLand HeL, respectively. While most ligands are be a free flowing or a viscous liquid, a non free flowing or predominately used as a HeL or predominately used as a LeL, thixotropic gel, or a solid or a semi-solid polymer. All of these there are exceptions which will be illustrated in the section Solvents provide enough mobility for the ligands to transfer in below on “LETC Reaction Equilibria” and in Table 27. and out of coordination with transition metal ions. 15 We understand that a LETC process occurs, as the tem The present application describes various LETC systems perature is raised, because a decrease in LeMLC concentra in which remarkable amounts of transition metal salts, ligand tion and an increase in HeMLC concentration takes place by salts, non-ionic ligands and other key additives are all dis a change in association of the ligands with the transition metal Solved at the same time in Solid polymer layers and remain in ion(s) in the MLC(s). Thus, an increase in temperature causes solution over the temperature range of interest of use. Not the number of transition metal ions in LeMLC(s) to decrease only can Such solutions be prepared, but select systems have and the number of transition metal ions in HeMLC(s) to been discovered that neither form precipitates nor do the increase. This results in a decrease in absorption at the wave layers develop haze over prolonged periods at elevated tem lengths absorbed by the LeMLC and an increase in absorption peratures, during numerous temperature cycles or during at wavelengths absorbed by the HeMLC. For the LETC sys extensive exposure to Sunlight or simulated Sunlight. 25 tems described herein, the result of these MLC transforma In the LETC systems of interest, transition metal ions in tions is a reversible, net increase in the systems ability to Solution are either Solvated, complexed, coordinated or absorb Sunlight energy as the temperature is increased. ligated by ions and/or molecules. The ions and/or molecules Some thermochromic systems in the literature are based on in the primary coordination sphere of the metalion are often the reversible loss and gain of water by a thermochromic referred to as ligands. For the purpose of the present applica 30 layer. However, in accordance with certain aspects of the tion, any ion or molecule that either Solvates, complexes, present invention, unless otherwise specified, the water con coordinates, ligates or directly interacts with a metal ion, in tent of the LETC systems of the present invention is kept as Such away that it impacts the light absorption character of the low as is reasonably possible. Also, whether or not water is system, is referred to as a ligand. Also any transition metalion present, it is believed that the LETC processes described in solution is considered to be in a complex or coordination 35 herein occur just because of the rearrangements in the way compound even if the coordinating power of the solvent or ions and molecules associate and not due to materials lost other ligands is relatively weak. Typically, the transition from or gained by the system. Thus, in accordance with metal is in the form of a cation. certain aspects of the present invention, all of the active ingre When a transition metal ion is surrounded by certain dients in the TC system remain in the same solution or layer ligands, a “metal-ligand complex’, (MLC), may be formed 40 which has low molar absorptivity throughout the visible and throughout the operation or use of the system. NIR range. This MLC is, herein, referred to as a “low eMLC'. For discussions of thermodynamics, molar absorption (LeMLC). When the same transition metalion is surrounded coefficients, etc. it is convenient to use concentrations in by other ligands, a MLC may be formed which has a higher molarity. For molarity we use the definition: “moles of solute level of molar absorptivity somewhere in the visible and NIR 45 per liter of solution' and designate molarity with the symbol, spectral region. This MLC is, herein, referred to as a “high “M”. However, for making up practical formulations it is eMLC, (HeMLC). The LeMLC and the HeMLC may absorb often convenient to use molality. The molality is independent at the same or some of the same wavelengths or at Substan of temperature whereas molarity is affected by the thermal tially different wavelengths. Both the LeMLC and the expansion of the solution. For molality we use the definition: HeMLC generally absorb fairly strongly in the UV, and while 50 "moles of solute per kilogram of solvent and designate mola changes in the amount and the wavelengths of UV light lity with the symbol. “m”. If concentration is reported in absorbed may be useful aspects of the LETC process the molality, the value for this concentration in molarity for this primary applications involve changes in the visible and NIR Solution may be determined by measuring the total Volume of absorption ability. The e in these designations refers to the the solution after it is prepared. molar absorption coefficient or molar absorptivity of the 55 The components of a LETC system include one or more MLC in solution. The units of liters/(molecm) are used for E. than one type of transition metal ion, one or more than one HeMLCs have an e of greater than or equal to 50 liters/ type of LeL, one or more than one type of HeL and a solvent (molecm) at some or at least one wavelength between 400 which provides the medium for the exchange process. The nm and 1400 nm. LeMLCs have an e of less than 50 liters/ solvent itself may act as a LeL or HeL. Alternatively, the (molecm) for all wavelengths between 400 nm and 1400 nm. 60 LeL's and/or the HeL’s may be a part of the solvent system Any ligand in a LeMLC is, herein, referred to as a low e that helps solubulize other constituents. ligand, LeL. Any ligand in a HeMLC is, herein, referred to as a high e ligand, HeL. When a ligand is not coordinated to a Transition Metal Ions transition metal in a LeMLC or a HeMLC, the determination of whether or not the ligand is a LeL or HeL is not so clear 65 Described herein are many particularly useful LETC sys sometimes. Thus for the sake of the present disclosure, the tems based on complexes with first row transition metals ions. determination of ligand type is made by the side on which the LETC systems comprising Fe(II), Co(II), Ni(II) and/or Cu(II) US 7,525,717 B2 9 10 ions are disclosed herein. In LETC systems, the transition nickel(II) nitrate hexahydrate, nickel(II) perchlorate hexahy metalions are considered electron acceptors. This means that drate, nickel(II) tetrafluoroborate hexahydrate the transition metal ions associate with electron donors in the Particularly useful sources of transition metal ions that are sense that Lewis acids associate with Lewis bases. This is complexes include without limitation: distinguished from the situation of complete electron transfer 5 bis(1-ethyl-1H-benzimidazole)diiodonickel(II): to an acceptor in which the acceptor is reduced. bis(acetylacetonato)nickel(II): Useful transition metal ion concentrations depend on (1) copper bis(6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-oc the desired levels of absorbance and absorbance change, (2) tanedionate); the path length, (layer thickness), of the LETC system, (3) the copper(II) hexafluoroacetylacetonate hydrate; e of the LeMLC and (4) the e of the HeMLC. If the e of the 10 dibromo (1'-ethyl-1-methyl-1H, 1'H-2,4'-bibenzimidazole) LeMLC is sufficiently low that its absorbance can be ignored, nickel(II): and ACT, w) is the desired absorbance at a higher tempera dibromo2,2'-propane-2,2-diylbis(1-pentyl-1H-benzimida ture of operation, (T,), at a particular w, then the metal ion zole) nickel(II): concentration, (in moles per liter), must be equal to or greater dibromo 6-methyl-N-(6-methylpyridin-2-yl)methyl-N- than ACT, w)/(e(HeMLC, )*b). Where b is the path length 15 pyridin-2-ylpyridin-2-amine nickel(II): or layer thickness in centimeters and e(HeMLC, ) is the dibromoN-butyl-1-ethyl-N-(1-ethyl-1H-benzimidazol-2- molar absorption coefficient of the HeMLC in liter/ yl)-1H-benzimidazol-2-aminenickel(II): (molecm) at W. For example, if an ACT, w)=1 is desired at an dibromo(N-butyl-N-pyridin-2-ylpyridin-2-amine)nickel(II): elevated temperature, the e of the HeMLC is 250 liters/ dibromo(N-pyridin-2-ylpyridin-2-amine)nickel(II): (molecm) at and the desired layer thickness is 0.05 cm, dibromobis 1-(3-phenylpropyl)-1H-imidazolenickel(II): then the minimum transition metal ion concentration would dibromobis(1-ethyl-1H-benzimidazole)nickel(II): be 0.08M, for the unlikely event that all the transition metal dibromobis(1-pentyl-1H-benzimidazole)nickel(II): ion could be shifted into the HeMLC. In practice the transi dibromobis(2,2-dimethylpropane-1,3-diol)nickel(II): tion metal ion concentration would have to be higher than dibromobis 2-ethyl-2-(hydroxymethyl)propane-1,3-diol 0.08M and preferably would be greater than or equal to 1.5 25 nickel(II): times the minimum. dibromobis(triphenylphosphine)nickel(II): Generally, if the e of the LeMLC is not too high and a thin dibromotris(2,2-dimethylpropane-1,3-diol)nickel(II): TC layer is desired, (as it normally is), then metal ion con diiodobis 1-(3-phenylpropyl)-1H-imidazolenickel(II): centration is made as high as possible while still leaving diiodobis 2-ethyl-2-(hydroxymethyl)propane-1,3-diol opportunity to provide enough HeL to give a ratio of HeL/ 30 nickel(II): Mergreater than 4, where the brackets are used to designate diiodobis(tricyclohexylphosphine)nickel(II): concentration and the subscript T designates the total concen diiodobis(triphenylphosphine)cobalt(II): tration, in any form in the system, in moles per liter. Thus diiodobis(triphenylphosphine)nickel(II): HeL and Me, are the total concentrations of various lithium tetrabromonickelate(II): types of HeL's and various types of Me in the system that 35 nickel(II) bromide-(2-methoxyethyl ether complex): could potentially participate in HeMLCs. The upper limit of nickel(II) bromide-(ethylene glycol dimethyl ether complex): transition metal ion concentration is determined to some tetrabutylammonium tetrabromonickelate(II): extent by the solubility limit of the transition metal ions in the tetrabutylammonium tetrachloronickelate(II): system, but more often by the solubility limit of the HeL tetrabutylammonium tetraiodonickelate(II): and/or the LeL in the system. For most applications it is 40 tetraethylammonium tetrabromocobaltate(II): desirable that the system remain free of precipitates and haze tetraethylammonium tetrabromonickelate(II): at all temperatures of use, throughout the useful life of the tetrabutylammonium triiodo4-(3-phenylpropyl)pyridine thermochromic system. nickelate(II); and Sources of transition metal ions include: hydrated and tetrabutylammonium triiodo(triphenylphosphine)nickelate anhydrous salts of first row transition metal ions. Other 45 (II). Sources are anhydrous complexes and complexes in which the The use of metal complexes can be advantageous because transition metal has a coordination number of four or six in just the act of preparing complexes often improves the purity the complex. Particularly useful anions for the transition of these sources of transition metal ions. Many simple tran metal salts and complexes are halides, carboxylates, nitrate, sition metal salts contain traces of hydroxides, oxides and perchlorate, tetrafluoroborate, phosphinates, hexafluoro 50 oxyhydroxides that cause haziness in thermochromic systems phosphate, hexafluoroarsenate, trifluoromethanesulfonate, prepared from these salts. Complex formation often largely bis(trifluoromethane)sulfonamide, tosylates and tetraarylbo eliminates or avoids these impurities. Also, many of the non rates. ligating impurities which might be presentina batch of ligand Sources of transition metalions include but are not limited material are often excluded when the complex is formed in to: chromium(III) chloride hexahydrate, cobalt(II) bromide, 55 the process of synthesizing the complex. Thus ligands added cobalt(II) chloride, cobalt(II) chloride hexahydrate, cobalt(II) as part of a complex are often more pure than ligands added iodide, cobalt(II) nitrate hexahydrate, cobalt(II) tetrafluo directly to the rest of the system. While complexes, once roborate hexahydrate, copper(II) acetate monohydrate, cop prepared, may be further purified, Surprisingly we have dis per(II) bromide, copper(II) bromide dihydrate, copper(II) covered that just preparing the complexes often eliminates chloride, copper(II) chloride dihydrate, copper(II) nitrate 60 many of the impurity issues that might otherwise detract from hemipentahydrate, copper(II) perchlorate hexahydrate, cop preparing stable, high performance thermochromic systems. per(II) trifluoroacetate hydrate, iron(II) bromide, iron(II) tet In addition, these complexes are often less hygroscopic than rafluoroborate, manganese(II) bromide, manganese(II) most simple metal salts which assists in preparing systems nitrate hexahydrate, nickel(II) bis(diisobutyldithiophosphi with low water content. Even complexes that are hygroscopic nate), nickel(II) bromide hexahydrate, nickel(II) carbonate 65 are often less prone to forming hydroxides, oxides and oxy hexahydrate, nickel(II) chloride hydrate, nickel(II) cyclohex hydroxides during storage as compared to metal salts like e.g. anebutyrate, nickel(II) iodide, nickel(II) iodide hexahydrate, simple halide salts. Significant advantages are also realized US 7,525,717 B2 11 12 with the use of complexes since these complexes are usually Some diols that are useful as LeL's are represented by the more readily dispersed and dissolved in polymers in the following structure: LETC layer production process. This facilitates the produc tion of uniform composition and uniform performance layers especially in the extrusion processes preferred for making R3 R2 V Rs LETC layers. V -CN / R c1 NC R6 Types of Ligands in LETC Systems OH OH In LETC systems, the ligands serve as electron donors. 10 This means that the ligands associate with transition metals in the sense that Lewis bases associate with Lewis acids. This is wherein R. R. R. R. Rs and R are independently selected distinguished from the situation of complete electron transfer from straight, branched, substituted or unsubstituted alkyl: from a donor in which the donor is oxidized. A definition for substituted or unsubstituted aryl; or substituted or unsubsti HeL's and LeL's is given above. However, a molecule or ion 15 tuted aralkyl. Some specific examples of the above structure may be a HeL under one set of conditions and a LeL under are: 1.3-Cyclohexanediol; 1,1-Bis(hydroxymethyl)cyclopro another set of conditions, and of course vice versa. Thus one pane; 2.2-Bis(hydroxymethyl)propionic acid; 2.2-Dibutyl-1, must look at the main or predominant equilibrium reaction 3-propanediol; 2.2-Diethyl-1,3-propanediol; 2.2,4-Trim equation of a LETC system to see if the ligand is a LeL or a ethyl-1,3-pentanediol; 2,4-Dimethyl-2,4-pentanediol; 2.4- Pentanediol: 2-Bromo-2-nitro-1,3-propanediol; Serinol: HeL. 2-Butyl-2-Ethyl-1,3-propanediol: 2-Ethyl-1,3-hexanediol; A given ligand may coordinate to a metalion at one or more 2-Methyl-1,3-propanediol; 2-Methyl-2,4-pentanediol; than one site around the metalion. Ligands that coordinate in 2-Methyl-2-propyl-1,3-propanediol: 2-Methylenepropane a single site are referred to as monodentate and ligands that 1,3-diol: 2-Phenyl-1,3-propanediol: Cyclohex-3-ene-1,1- coordinate in multiple sites are referred to as polydentate. As diyldimethanol: 3-Methyl-1,3-butanediol. 3-Methyl-2,4- the names signify, bidentate, tridentate, tetradentate and 25 hexadentate ligands coordinate in two, three, four and six heptanediol; 2-(2-phenylethyl)-1,3-dioxane-5,5-diyl sites, respectively. dimethanol; Neopenty1 Glycol; and Trimethylolpropane allyl Metal ions may be coordinated by ligands of a single type ether. like many well known hexa-aquo coordinated ions in which Some triols that are useful as LeL's are represented by the six water molecules Surround a metal ion or when four of a 30 following structure: single type of halide anions Surround a metal ion as in a tetrahalo-metalate complex. These are known as homoleptic complexes. However, many heteroleptic, (mixed ligand), R complexes are known where two or more different ligand HOCH-C-CHOH types coordinate to the same metalion at the same time. For 35 example, a heteroleptic complex is formed when the ligands CH2OH around a single metal ion consist of two iodide ions and two molecules of some type of phosphine compound which coor dinates to metal ions through phosphorus. This is illustrated wherein R is selected from straight, branched, substituted or for increases in concentration with increasing temperature for 40 unsubstituted alkyl; substituted or unsubstituted aryl; substi Co(II)L(PhP) in FIG.9 and for Ni(II)L(PhP) in FIG. 27. tuted or unsubstituted aralkyl, a nitro group; or a substituted Another example is iodide ions and trifluoroacetate ions coor or unsubstituted amino group. Some specific examples of the dinated at the same time to Co(II) ions as shown in FIG. 4. above structure are: 2,2'-(propane-1,3-diyldiimino)bis 2 Many other TC systems that involve heteroleptic HeMLC's (hydroxymethyl)propane-1,3-diol: 2-bis(2-hydroxyethyl) are listed in Table 27. 45 amino-2-(hydroxymethyl)propane-1,3-diol; Dipentaeryth ritol; Pentaerythritol: 2-(bromomethyl)-2-(hydroxymethyl) LeL propane-1,3-diol: 2-(hydroxymethyl)-2-propylpropane-1,3- diol; 2-(hydroxymethyl)-2-methylpropane-1,3-diol; The best LeL's promote the formation of LeMLCs with 2-(hydroxymethyl)propane-1,3-diol: 2-(hydroxymethyl)-2- the least amount of absorbance, (lowestes), and help pro 50 nitropropane-1,3-diol; Trimethylolpropane; 2-amino-2-(hy mote the highest positive values of AH and AS for the LETC droxymethyl)propane-1,3-diol. reaction, (as discussed later). They also help solubilize other Depending on the transition metal ion, the HeLs, the liq system components and help provide desirable physical prop uid or polymer solvent used in the LETC system, the follow erties to TC layers when the layer involves a polymeric mate ing list of LeL’s may also be useful: Di(Trimethylolpropane); rial which comprises the rest of the TC system. 55 L-Fucose: meso-Erythritol; N-propyl-N-pyridin-2-ylpyri Hydroxyl groups attached to carbon provide LeL function din-2-amine: Poly(vinylbutyral): Poly(vinylpyrrolidone); ality. The MLC's, formed by coordination of ligands to tran Tetrahydrofurfuryl alcohol; Tetrahydropyran-2-methanol: sition metals through hydroxyl groups, tend to have some of Triethanolamine; 1,2,4-Butanetriol: 1,2-phenylenedimetha the lowest values fore throughout the visible light wavelength nol; 1.2-Hexanediol; 1.2-Propanediol; cis,cis-1,3,5-Cyclo range. In general, the useful LeL's for LETC systems include 60 hexanetriol: 1,3,5-Pentanetriol; 2.5-bis(hydroxymethyl)-1,4- water, diols, triols or polyols. Water is a useful LeL or co-LeL dioxane-2,5-diol: 1,4-Butanediol: 1,4-Cyclohexanediol; when Fe(II) and/or Cu(II) ions are used in the LETC system. 18-Crown-6: 2,3-Dimethyl-2,3-butanediol: 2-Phenyl-1,2- While water is a useful LeL with regard to good thermochro Propanediol: 3-(Diethylamino)-1,2-propanediol: 2-ethyl-2- mic performance with other transition metal ions, it is to be (hydroxymethyl)butane-1,4-diol: 3,3-Dimethyl-1,2-butane avoided or limited to low concentrations in most LETC sys 65 diol: 3-Hydroxypropionitrile; 3-Methyl-1,3,5-Pentanetriol: tems because of its relatively low boiling point and its reactive 3-Phenoxy-1,2-Propanediol, 4-Hydroxy-4-methyl-2-pen nature. tanone; 3-Phenyl-1-propanol; (5-methyl-1,3-dioxan-5-yl) US 7,525,717 B2 13 14 methanol; Bis(methylsulfinyl)methane; Butyl sulfoxide: which participate in equilibrium reactions with the transition Diethylene glycol; Diethylformamide: Hexamethylphos metal ions and the LeL’s wherein there are high positive phoramide; 3,3'-oxydipropane-1,2-diol; Dimethyl sulfoxide: values of AH and AS for the overall LETC reaction. Ethanol; Ethylene Glycol; Glycerol: Glycolic Acid; 3-(2- Described herein are particularly high performance LETC methoxyphenoxy)propane-1,2-diol; Lithium Salicylate; systems involving iodide ions as a HeL. High performance Lithium Trifluoroacetate; N.N-Dimethylformamide; 1,1,3,3- Tetramethylurea; 2.2-dimethylpropan-1-ol; Pentaethylene LETC systems are also disclosed wherein phosphine mol glycol; Pentaerythritol ethoxylate; tetrahydrothiophene 1-ox ecules which coordinate through a phosphorus are used as ide; Tributylphosphine oxide; Trimethylolpropane ethoxy HeLs. Examples of these phosphine compounds include eth late; Trimethylolpropane propoxylate; Triphenylphosphine 10 yldiphenylphosphine, triphenylphosphine and tricyclohexy oxide. lphosphine. Particularly high performance LETC systems When the transition metalion is NiCII) and the use of water involve phosphinates as HeL’s. Particularly high perfor as a LeL is problematic, C. and especially B diols are useful mance LETC systems are also described involving phosphine LeL’s. A diol is an O. diol when two hydroxyl groups are compounds and iodide in combination and these HeL's in present on adjacent carbons like in 2,3-butantediol. A diol is 15 combination with other HeL’s. The present application a B diol when two hydroxyl groups are present on carbons separated by an additional carbon like in 1,3-butanediol. In describes LETC systems in which a HeL is a five membered, many cases, these C. and B diols act as bidentate ligands and heterocyclic, organic ring compound which coordinates to a they are more useful than triols because the diols, especially transition metal through nitrogen. These ligands have advan Bdiols, give higher positive values of AH and AS for LETC tages over six membered ring compounds which coordinate reactions involving Ni(II) ions and most HeL’s. In most cases through nitrogen in that they are more likely to allow TC the triols act as tridentate ligands and occasionally they areas activity at 550 nm, which is near the peak of human eye useful as diols with Ni(II) based systems because lower con sensitivity for light. Other advantages of various ligands are centrations of triols are required which may result in easier described below. processing of the systems which involve polymer layers. 25 In general, triols are useful LeL's for Co(II) ions in appli Not only do iodide and phosphine compounds like PhP cations where the use of water is problematic. Triols may be and other triaryl, trialkyl mixed aryl/alkyl phosphines, when more useful than diols with Co(II) because the tridentate used together, form HeMLCs with large values of e, we have nature of the triols allows them to better compete for com discovered a special effect where an excess of PhP can plexation of Co(II) ions and thus form higher performance TC 30 minimize or eliminate undesirable residual color in a TC layer systems which also comprise most HeL's of interest for use produced with these ligands. Presumably this is because the with Co(II) ions. With Co(II), the amount of diol required to phosphine compound sequesters a small amount of residual I compete with most HeL's is too high for most practical appli and thus prevents the appearance of a yellow color due to free cations involving LETC systems in polymer layers. If the iodine. This free iodine may be the result of air oxidation of concentration requirement for LeL is too high, either that 35 iodide during processing and this problem is mitigated when amount of LeL is above the solubility limit or it is difficult to uniformly disperse in the LETC layer. Alternatively, too an excess of a phosphine compound is present. This syner much LeL may make it difficult to produce a LETC film or gistic effect with or without the use of seals to minimize the sheet, by e.g., extrusion, because of poor physical properties ingress of oxygen has allowed for the use and production of like softness, tackiness, streaks and non-uniform thickness. 40 these high performance, LETC systems. In addition, it has LeL character may also be provided by the hydroxyl been discovered that even when the phosphine compound is groups on various polyol polymers like hydroxyethyl cellu not intended to be used as a ligand, that an amount of phos lose, hydroxypropyl cellulose, poly(vinyl butyral), poly(vi phine compound less than Stoichiometric to the amount of nyl alcohol) and poly(hydroxyalkylmethacrylates and acry transition metal ion can be used when iodide is a used as a lates). Some of these polymers even provide f diol type 45 ligand. Eventhese Small amounts of phosphine compound are functionality. useful to mitigate the effects of residual color formation dur Acceptable concentrations of LeL's are determined by the ing processing of these TC systems into layers. concentrations of the transition metal ions and the ratio of HeL's to transition metal ions. The temperature range of the Useful concentrations for HeL's are largely dependent on application and the effectiveness of the Le L. (i.e. the stability 50 the transition metal ion concentrations used in the LETC constant for the formation of the LeMLC), are also important system. Generally it is useful to have a HeL concentration as in determining useful concentrations. A specific LeLand its high as is chemically possible and/or economically possible. concentration are often chosen such that the absorbance of the Specifically it is useful that the concentration ratio for the LETC layer is less than 0.2 at 25 C and the absorbance still HeL's to transition metal ions be greater than 4 and in many increases to greater than 0.8 at 85 C. These absorbance 55 cases that the ratio be greater than 7. This is the ratio for the changes are for the active wavelength range, (at least at one of total concentration of all HeL's, HeL, to the total concen the values), of a HeMLC in the LETC system. tration of all transition metal ions, Me, which together HeL could potentially be involved in forming HeMLCs. The 60 advantages of high ratios of HeL's to metalions are discussed Particularly useful HeL's include the halides: chloride, below. bromide and iodide and pseudohalides like cyanate, thiocy Ligands containing a nitrogen-containing 5- or 6-mem anate, selenocyanate, azide and cyanide. Other particularly bered heterocyclic compound that coordinates through the useful HeL's include molecules or ions which coordinate to nitrogen atom to the nitrogen transition metal ion in an transition metal ions through nitrogen, oxygen, phosphorus, 65 HeMLC formed between the transition metal ion and the sulfur and/or selenium. The preferred HeLs are those which ligand are particularly useful. Examples of these ligands provide for the higheste for the HeMLC formed and those include those having the following structure: US 7,525,717 B2 15 16

2^ 's X Xs \ilX-X wherein X and X are each independently selected from the wherein X=N H. N. R. O, S, or Se and wherein RandR group consisting of C. C. R. N. and N—R: X is C or C R: are independently chosen from Straight or branched, Substi X is C, C R. N. N. R.O.S or Se:Xs is C, N, S, C R, each 10 R is independently selected from the group consisting of tuted or unsubstituted alkyl; substituted or unsubstituted aryl; hydrogen, Substituted or unsubstituted Straight or branched or substituted or unsubstituted aralkyl. alkyl, Substituted or unsubstituted aryl, aralkyl, and combi Other HeL's that coordinate to transition metals though a nations thereof, provided that optionally two or more R nitrogen in a five membered ring are imidazo 1.5-alpyridine; groups may be joined to form one or more Substituted or 15 imidazol-2-alpyridine; 1,2,4-triazolo 1.5-alpyrimidine; unsubstituted fused saturated or unsaturated ring systems. 2,1,3-Benzothiadiazole; 5-aZabenzimidazoles; and 4-aza Certain HeL’s ligands coordinate more strongly and form benzimidazoles. coordination compounds that absorb at certain desirable Bidentate HeL's in which heterocyclic nitrogen containing wavelengths, especially in the 550 nm region, when there is a groups are bridged by alkyl, amine, amine-methylene or ben nitrogen in a 5 membered ring. Some of these HeL's that are Zene as a spacer are represented by the following structure: imidazoles, oxazoles, thiazoles or selenazoles are represented by the following structure: 1 n R R2 25 !---N N---.: 1N,y ( N-R, X = (CH2), n = 1 to 4

30 wherein X=N H. N. R. O, S, or Se and wherein RandR N-H, -N-CH are independently chosen from straight or branched, substi tuted or unsubstituted alkyl; substituted or unsubstituted aryl; or substituted or unsubstituted aralkyl. Some of these HeL's that are pyrazoles, isoxazoles, 35 wherein R. R. R. R. and Rare independently chosen from isothiazoles, or isoselenazoles are represented by the follow straight or branched, substituted or unsubstituted alkyl; sub ing structure: stituted or unsubstituted aryl; or substituted or unsubstituted aralkyl. and wherein each R 40

Y.M R X

45 wherein X=N H, N-R, O, S, or Se and wherein R, R and R2 are independently chosen from Straight or branched, Sub independently represents a nitrogen-containing five or six stituted or unsubstituted alkyl; substituted or unsubstituted membered ring and in certain cases is independently chosen aryl; or substituted or unsubstituted aralkyl. from substituted or unsubstituted imidazole, pyridine, benz Some of these HeL's that are benzimidazoles, benzox 50 imidazole, benzothiazole, indazole, pyrazole, etc. azoles, benzothiazoles, or benzoselenazoles are represented HeL's that function as tridentate ligands that coordinate by the following structure: with 3 nitrogens are represented by the following structure:

55 21 N o N * > - - - -C-X Y-C------N N- - - - 60 wherein X=N H. N. R. O, S, or Se and wherein RandR are independently chosen from Straight or branched, Substi wherein X and Y are independently chosen from (CH), n=1 tuted or unsubstituted alkyl; substituted or unsubstituted aryl; to 3: R=straight or branched, substituted or unsubstituted or substituted or unsubstituted aralkyl. alkyl; substituted or unsubstituted aryl; or substituted or Some of these HeL's that are indazoles, benzisoxazoles, 65 benzoisothiazoles, or benzoisoSelenazoles are represented by unsubstituted aralkyl: the following structure: and each US 7,525,717 B2 17 18 and R. R. R. R. and R are independently chosen from substituted or unsubstituted, straight or branched alkyl; sub stituted or unsubstituted aryl; or substituted or unsubstituted aralkyl; and independently represents a nitrogen-containing five or six membered ring and in certain cases is independently chosen from substituted or unsubstituted imidazole, pyridine, benz 10 imidazole, benzothiazole, indazole, pyrazole, etc. HeL's that can coordinate in multiple bidentate configura tions are represented by the following structure: each independently represents a nitrogen-containing five or six membered ring and in certain cases is independently cho 15 sen from substituted or unsubstituted imidazole, pyridine, F--- benzimidazole, benzothiazole, indazole, pyrazole, etc. In many of the structures above, Zl F----X1|| Y------N N- - - - may be replaced by NRR, where R and R are indepen 25 dently chosen from substituted or unsubstituted, straight or wherein only 1 or 2 of X,Y and Z are (CH), n=1 to 2 and the branched alkyl; substituted or unsubstituted aryl; or substi others are a direct bond between N and the ring C, and each tuted or unsubstituted aralkyl. HeL's that coordinate via a mercapto group and an imine type nitrogen are represented by the following structure: 30 independently represents a nitrogen-containing five or six membered ring and in certain cases is independently chosen 35 from substituted or unsubstituted imidazole, pyridine benz imidazole, benzothiazole, indazole, pyrazole, etc. wherein X=N H, N-R, O, S, or Se and R=substituted or HeL's that are ortho hindered pyridines are represented by unsubstituted, straight or branched alkyl; substituted or the following structure: unsubstituted aryl; or substituted or unsubstituted aralkyl. 40 HeL's that are phosphine compounds are represented by the following structure:

45 R P

wherein R=halide; substituted or unsubstituted, straight or 50 wherein R, R2 and R are independently selected from alkyl, branched alkyl; substituted or unsubstituted aryl; or substi cycloalkyl, or substituted or unsubstituted aryl. tuted or unsubstituted aralkyl. In many cases, HeMLCs that involve the ligands with the HeL's that function as bidentate ligands via an amine type structures above, also involve halides or pseudohalides in the nitrogen and an imine type nitrogen are represented by the same HeMLCs. Other useful HeL's are given in the key following structure: 55 Section of Table 27. Solvents R M F-- -x-x wherein X = (CH), n=1 to 4, In LETC systems, any solvent that provides for and main 60 tains the dissolution of the metal salt complexes and ligands, i. R2 allows for the change or exchange of ligands to take place and R R2 R3 R4 does not detract from the reversibility or stability of the sys y ( N-R O tem is acceptable. Some of the solvents that we have found, 1 n -N-CH which meet these criteria, are liquids at 25 C. These include 65 polar organic solvents like acetonitrile, glutaronitrile, 3-methoxypropionitrile, sulfolane, 1,1,3,3-tetramethylurea, dimethylsulfoxide, hexamethylphosphoramide, e-caprolac US 7,525,717 B2 19 20 tone, dimethylformamide, ethylene glycol, and propylene Generally when a set of ligands coordinates at four sites glycol. In many cases it is effective to have a relatively indif around the metalion, the MLC has a higher molar absorptiv ferent solvent with respect to metal ion complexation like ity in the visible and/or NIR. This ligand configuration may be propylene carbonate or Y-BL so that the LETC equilibrium is referred to as tetra-coordinate and generally gives the com established largely by the interaction of the LeL's, the HeL's plex a tetrahedral configuration, a square planar configuration and the transition metal ions dissolved in the solvent. or distorted versions thereof sometimes referred to as pseudo Other effective solvents, that are polymers, include poly tetrahedral or pseudo Square planar. Generally, the higher (vinylalcohol); copolymers of poly(vinylalcohol) with vinyl molar absorptivity of these complexes is due to more highly acetate, methylmethacrylate, ethylene and the like; poly(vi allowed electronic transitions between molecular orbitals of nyl acetals) including poly(vinylbutyral); cellulose acetates; 10 predominately metal d-orbital character. Occasionally the urethanes; hydroxyalkylcelluloses; hydroxy-substituted tetra-coordinate complexes have very strong absorbances due polyacrylates like poly(hydroxyethyl methacrylate) and poly to charge transfer transitions in the visible portion of the (1-glycerol methacrylate); poly(2-ethyl-2-oxazoline); poly spectrum and we have discovered that these can be used to (N-vinylpyrrolidone); poly(vinyl methyl ether); polyacryla great advantage in LETC systems. Whether or not a set of mide; poly(N,N-dimethylacrylamide); polyvinylpyridines 15 ligands gives rise to a tetra-coordinate configuration, if the and various copolymers which involve these polymer func MLC that increases in concentration on heating has an e of tionalities. Also useful are solvent systems which involve a greater than 50 liters/(molecm) anywhere in the visible or combination of one or more than one of the solvents, which NIR region then it is hereby defined as a HeMLC. are liquids at 25C, dissolved in a polymer. Particularly useful Given the definitions above for LeMLCs and HeMLC's, a are polymers that form solutions of LETC systems that will few LETC thermochromic systems of interest actually func not flow under the influence of gravity alone in the tempera tion by having one HeMLC change into another HeMLC. In ture range of 0 to 100 Celsius. Polymers that form solutions of one system like this, the HeMLC that dominates at lower LETC systems that are solids in the temperature range of 0 to temperatures absorbs mainly in the NIR and the HeMLC that 100 Celsius are particularly useful. dominates at high temperatures absorbs mainly in the visible The solvent may also be the solid matrix portion and/or the 25 portion of the spectrum. See Table 27, entry 359. liquid Solution portion of a gel. In a “chemical gel there is a Another system like this has a HeMLC that dominates at liquid phase and a solid matrix phase. The solid matrix phase lower temperatures with a modest absorptivity in the visible may be an inorganic polymer like in a common sol-gel or it and has a HeMLC that dominates at high temperatures with a may be an organic polymer which is crosslinked or a star higher absorptivity in the NIR. SeeTable 27, entries 406,457, polymer which forms a three dimensional network. The liq 30 861 and 901. uid phase for a LETC system is preferably one or more of the Apart from octahedral and tetrahedral configurations, liquids at 25 C listed above. The gel may be a chemical gel MLC's are known in which three, five, seven, eight or even including a "molecular gel” or a physical gel. For a more more sites around a metalion are coordinated. In these cases, detailed discussion of gels see: Electrochimica Acta 46, 2015 we use the same criteria as above to distinguish between them 2022 (2001). 35 as LeMLC's and HeMLCs. In principle, the solvent may be a molten salt including a LeMLC's include Cu(H2O)" and Fe(HO)". LeMLC's low temperature or room temperature ionic liquid. include Ni(II) and Co(II) coordinated by diols, triols or poly Certain LeL's, especially diols, triols and polyols, are ols. Some LeMLCs are coordination compounds with likely effective in promoting solubility of other materials in the formulas: Ni(TMOLP)", Ni(2-(hydroxymethyl)-2-methyl LETC system. Also, some of these LeL's are good plasticiz 40 propane-1,3-diol)". Ni(cis,cis-1,3,5-cyclohexanetriol).", ers for the polymers that serve as cosolvents and matricies in Ni(NPG)", Ni(2,4-dimethyl-2,4-pentanediol)", Ni(3-me LETC systems. thyl-1,3,5-pentanetriol)", Ni(poly(vinyl butyral))", Co(T- MOLP)*, Co(NPG), Co(2,4-dimethyl-2,4- Types of MLC's pentanediol).", Co(cis,cis-1,3,5-cyclohexanetriol).", 45 Co(poly(vinyl butyral))". In addition LeMLC's are useful The spectra of many MLC's are relatively well understood; when diols, triols and polyols are at least partially coordinated see for example “Inorganic Electronic Spectroscopy” by A. to the transition metal ions as is often the case with Ni(II) B. P. Lever, Elsevier Publishing Co. (1968) and (1984) and based systems that also contain nitrogen based ligands. “Inorganic Chemistry”, 3" Edition, by G. L. Miessler and D. Some HeMLC's include FeBr; CoC1 (S); CoBr(S); A. Tarr, Prentice Hall (2004). Generally when a set of ligands 50 CoI,(S); NiC1 (S); NiBr(S); NiI,(S); CoC1; coordinates at six sites around the metal ion, the MLC has CoBr; Col; NiC1; NiBr; NiI: Cu(S)C1; lower molar absorptivity values in the visible and NIR. This complexes of Co(II), Ni(II), or Cu(II) with ligands which ligand configuration may be referred to as hexa-coordinate coordinate to metal ions through pseudohalides, nitrogen, and generally gives the complex an octahedral or nearly octa oxygen, phosphorus, Sulfur or selenium; and complexes of hedral configuration. Often, there are some relatively strong 55 Co(II), Ni(II), or Cu(II) with combinations of halides or absorbances in the UV even with hexacoordinate complexes pseudohalides and ligands which coordinate to metal ions due to charge transfer type absorptions. However, absor through nitrogen, oxygen, phosphorus, Sulfur or selenium. bances due to transitions of electrons between molecular The nitrogen, oxygen, Sulfur and selenium may be neutral in orbitals of predominately metal d-orbital character in octahe charge or they may have a formal negative charge, (i.e. they dral MLCs are generally quite weak. Furthermore, the pho 60 may be part of an anion). In the above formulas, (S), repre tons capable of causing Such electronic transitions are almost sents a solvent molecule, a hydroxyl group or an unknown exclusively in the visible and NIR. Whether or not a set of ligand. One, two, three or four halides of the same type or of ligands gives rise to a hexa-coordinate or octahedral configu two or more types, (e.g. both bromide and iodide), may be ration, if a MLC which decreases in concentration on heating coordinated to the same metal ion at the same time. Some has an e of less than or equal to 50 liters/(molecm) through 65 HeMLC's involve Co(II) or Ni(II) coordinated to ligands out the visible and NIR range of 400 nm to 1400 nm, then it is based on pyridine derivatives, pyridazines, dipyridyl deriva hereby defined as a LeMLC. tives, dipyridylamines, imidazoles, bisimidazoles, indazoles, US 7,525,717 B2 21 22 pyrazoles, benzimidazoles, bisbenzimidazoles, phosphines, Me(mono-dentate).’"--4X *Mexi+6(mono-den phosphinates, thiols, thiol ethers and especially these ligands tate) (2) in combination with chloride, bromide and/or iodide. HeM LC's include complexes with ligands that may be mono, bi, tri Me(bi-dentate), '+4X-MeX, +3(bi-dentate) (3) or tetradentate. HeMLCs include complexes with ligands based on nitro Me(tri-dentate).’"+4X PMex2+2 (tri-dentate) (4) gen as a heteroatom in a five membered, organic, ring com For the present disclosure all of the LETC equilibria reac pounds. Nitrogen based ligands in five membered rings have tions are written such that the LeMLC is on the left and been discovered to form LETC systems with higher perfor HeMLC is on the right of the mass balance, equilibrium mance, more desirable wavelengths of activity, especially in 10 equation. In equilibria reactions (2) through (4), X is a HeL the 550 nm region and/or they are lower cost than many and the metal ion is changing from hexa-coordinate to tetra ligands based on nitrogen as a heteroatom from six mem coordinate. The change from hexa to tetra-coordinate is use bered, organic, ring compounds. Cost considerations aside, ful but is not required in LETC systems. these advantages may be due to less steric hinderance for As used herein, transition metalions in Solution are always involvement by nitrogen from five membered ring com 15 considered to be complexed or ligated, since even when free pounds versus those in six membered ring compounds. On the in solution, transition metal ions are considered to be coordi other hand for providing absorption peaks in certain other nated by the solvent. However, ligands may participate in a wavelength regions HeMLC's involving ligands with nitro complex or they may be free in solution where the ligands are gens in six membered rings are still useful. Also, we have not coordinated but are simply Solvated. Thus, with many discovered HeMLC's with absorption peaks at desirable LETC systems like those above, the ligand exchange is sim wavelengths that involve ligands with nitrogens in six mem ply between one type of LeL either being ligated to a metal bered rings like pyridine which have a Substituent in a posi ion or being free in Solution and one type of HeL either being tion ortho to the nitrogen. These ligands coordinate to transi free in solution or being ligated to a metal ion. A specific tion metals with a strength that makes them desirable for example of just one of the types of equilibrium reactions that combining with other HeMLCs that form in the same solu 25 fit the above description is given below: tion and give TC activity over the same temperature range. In Ni(TMOLP),?"+4 CIPNiCl2 +2(TMOLP) (5) addition, these ortho substituted pyridine and pyridine like ligands are less likely to participate in LeMLC's than unhin (light green) (blue) derd versions thereof and this results in lower es for the NiCL is a well know MLC from the literature and it is a LeMLCs. Quinoline and it derivatives are naturally ortho 30 HeMLC. Ni(TMOLP) is a LeMLC. It is unlikely that the substituted pyridines and thus are effective in forming HeM reaction in equation 5 proceeds in a single step. However in LC’s with these advantages. many cases the observed changes in absorbance with tem Table 1 shows the HeMLC's for thermochromic systems perature point to a main or predominant overall reaction like where the HeMLCs are based on just Ni(II) ions, a few that shown in equation (5). nitrogen containing ligands and bromide. With good LeL's in 35 Under some conditions with, for example, a cobalt-halide these TC systems, we obtain large absorbance increases with system, the observed spectral changes point to equilibria that increasing temperature over the range 25 C to 105 C are are bit less straight forward. In the specific case in equation obtained. Remarkably, these absorbance increases have (6) below, the LeL, 1,3-butanediol, of the LeMLC may was that range all the way from 435 nm to 781 nm. remain partially coordinated to the Co(II) and thus participate 40 in the HeMLC. This is represented by the 1,3-butanediol TABLE 1. in the formula below. For the sake of convenience, the par tially coordinated diol is now said to be a HeL. The bromide, max max max on the other hand, is the primary HeLand when the bromide values values values Most Likely HeMLC (nm) (nm) (nm) is not coordinated to the Co(II) it appears on the same side of 45 the equation as the LeMLC, Co(1,3-butanediol)". Ni(N-Pr-dipicoylamine).Br. 435 523 717 Ni(N-Bu-di(1-MeBIMZ-2- 450 544 781 Co(1,3-butanediol), '+3Brico(1,3- ylmethyl)amine).Br. butanediol)Brs' +2(1,3-butandiol) (6) Ni(N-Pr-DPamine)Br, 502 557 Ni (2,2'-propane-2,2-diylbis(1-propyl-1H- 503 568 (light pink) (blue) benzimidazole).Br. 50 Here the term 1,3-butanediol is used to designate the Ni (2,2'-methylenedipyridine)Br, 520 1,3-butanediol as acting as a bidentate ligand and the term Ni (2,2'-ethane-1,2-diyldipyridine).Br. S48 610 Ni (2,2'-propane-1,3-diyldipyridine).Br. 556 636 1,3-butanediol is used designate a 1,3-butanediol mol Ni(1-EtBIMZ).Br. S8O ecule still attached to the Co(II) but now in a monodentate Ni(4-(3-PhPr)Pyr)Br, 631 fashion where essentially one hydroxyl oxygen is still coor Ni(isoquinoline).Br. 633 55 dinated. Ni(1-EtBIMZ).Br. 640 Ni(ROH).Br. 659 More involved LETC reaction equilibria yet are repre NiBr? 706 757 sented by the following equations: Ni(N-P-DPamine)(NPG),?"+4CI-NiCl2 + (N Pr-DPamine)+2NPG (7) Many more examples of LETC systems, with activity at a 60 wide variety of wavelengths, are given in Table 27. Ni(N-P-DPamine), '+4CI-NiCl2 +3N Pr DPamine (8) LETC Reaction Equilibria Ni(N-Pr-DPamine)C1-2CI-NiCl2 +N-Pr DPamine (9) Some generalized ligand exchange reactions with mono 65 dentate, bidentate, and tridentate LeL's are given by the fol Ni(N-P-DPamine)(NPG),?"+2CI-Ni(N-Pr lowing equations: DPamine)Cl+2NPG (10) US 7,525,717 B2 23 24 Ni(N-Pr-DPamine),"+2CI-Ni(N-Pr-DPamine) are those shown in equation (12) or (13) or a combination of Cl+2(N-Pr-DPamine) (11) these two reactions as shown in equation (14) below. From the best of our understanding of this system, Ni(N— Ni(1-EtBIMZ)(TMOLP)(TMOLP)* + Pr-DPamine)(NPG)" and Ni(N-Pr-DPamine)" are pos 5 3.Br. Ni(1-EtBIMZ)Br, +2(TMOLP) (12) sible LeMLCs. The amount of each of these LeMLC's present depends on the relative amounts of Ni(II) and espe Ni(1-EtBIMZ)(TMOLP)(TMOLP)?"+2Br + cially the relative amounts of NPG and N—Pr-DPamine to 1-EtBIMZNi(1-EtBIMZ), Br-2(TMOLP) (13) each other and to the amount of Ni(II). However, the spectra at lower temperatures do not appear to show the presence of 10 Ni(NPG)'" when there is one N-Pr-DPamine per Ni(II) present. This is the case even with an excess of NPG present. This is unfortunate in that the absorption coefficient for TMOLP, and TMOLP represent TMOLP acting as a Ni(N-Pr-DPamine)(NPG)" is somewhat higher than that tridentate ligand and as a bidentate ligand where only two of 15 its hydroxyls are coordinated, respectively. The relative of Ni(NPG)". This is very similar to the absorbance shown amount of Ni(1-EtBIMZ), Br, versus NiC1-EtBIMZ).Br. in FIG. 18 at 25C in the 550 nm to 775nm region for the very may be adjusted by judicious choices of the relative amount similar LETC system with Ni(II), N Pr-DPamine, bromide of bromide vs. 1-EthBIMZ in the system. Large amounts of and TMOLP. LeMLC's like Ni(N Pr-DPamine)(NPG), bromide relative to 1-EtBIMZ favor the formation of NiBr. result in more absorbance or a darker color than desired at (1-EtBIMZ), however even very large excesses of bromide lower temperatures even though the system has reasonably do not result in the appearance of the spectra of species like good performance otherwise due to a significant increase in NiBr(S)' or NiBra when there is at least one 1-EtBIMZ absorbance or a darkening in color as the temperature molecule per Ni(II) ion present. increases. Many heteroleptic MLC's are known which involve two or In the system of equations (7)-(11), NPG is a LeL and 25 more different ligands on the same transition metalion, how chloride is a HeL. N. Pr-DPamine is both a LeLand a HeL. ever very few reversible, solution based, thermochromic sys NiCl, and Ni(N-Pr-DPamine)C1, are HeMLCs. With tems involving ligand exchange to form Such heteroleptic properly chosen levels of chloride, NPG and N—Pr-DPam MLCs have been previously disclosed. Two of these dis ine, either NiCl, is the main HeMLC formed on heating or closed here are shown in the equations (12) and (13) and we it is possible that heating results in an absorbance increase 30 have discovered many more of these systems which are dis that can be attributed almost exclusively to the complex: closed in Table 27. Through the use of these systems, absorp Ni(N-Pr-DPamine)Cl. Remarkably, these HeMLC's can tions can be achieved throughout the visible and NIR range also form simultaneously on heating over the same tempera which is advantageous from an energy absorbing standpoint, ture range with the properly chosen concentrations and ratios especially for Sunlight blocking applications. of the materials in equations (7)-(11). Despite the rather com 35 A number of our LETC systems give rise to multiple HeM plicated equilibria possible, this system illustrates the diverse LC's from the heating of a single composition, even with only performance possible when concentrations and concentration a single type of transition metal ion present. Another good ratios are judiciously adjusted. example of this is seen with Ni(II), bromide, N Pr-DPamine As shown above, a ligand that is primarily used as a HeL with various LeL’s. With the proper ratio of bromide to may remain in place in the LeMLC. This is the case with 40 N—Pr-DPamine, heating the system gives rise simulta many heterocyclic ligands in which nitrogen is the heteroa neously to absorption spectra consistent with the presence of tom. For example, solutions of Ni(II) with bromide and 1-Et Ni(N-Pr-DPamine)Br, NiBr(S) and NiBr. This type BIMZ, appear to form two different HeMLC's each of which of performance for a LETC system is shown in FIG. 18. The is a different shade of blue. One of these complexes is broad spectral changes that take place on heating systems like believed to have two bromides and two of the benzimidazoles 45 these have distinct advantages when there is a desire to relieve coordinated to the nickel and has significant absorbance at glare or reduce energy transmission throughout the visible 550 nm. The other is believed to have three bromides and one and NIR regions. Broad changes also help provide valuable benzimidazole coordinated to Ni(II) and has little absorbance options for the color appearance of transmitted light. These at 550 nm. Addition of a good LeL like TMOLP to a solution systems that allow for multiple HeMLCs to form in a single containing either or both of these complexes decreases the 50 composition also provide opportunities to reduce the number intensity of the blue color. However, a small, (but significant of LETC layers required for many applications. Numerous with regard to overall performance), absorption peak at about other systems like this are disclosed in Table 27 and several of 640 nm remains even with a large excess of TMOLP. An these systems are shown in FIGS. 4, 14, 17 and 28. absorption peak with this shape and apparent molar absorp Once again, with systems like those in equations (12)-(14), tivity is not present for Ni(II) complexed with TMOLP alone 55 a nitrogen containing ligand may be present in the LeMLCs. or when Ni(II) and bromide are present with or without When this is the case, the e's of the LeMLC are generally TMOLP. This suggests that at least one, difficult to displace, larger than if just hydroxyl groups are present around the molecule of 1-EtBIMZ is present in the LeMLC. While the metalion. This higher level of absorptivity is a disadvantage 1-EtBIMZ is present in the LeMLC, it is designated as a LeL. for LETC systems where a large absorbance range is desired. Heating a system with appropriate ratios and amounts of 60 This is because for many applications there is a desire to start Ni(II), bromide, 1-EtBIMZ and TMOLP contained in an with as little absorbance or as light a color as possible at low indifferent solvent or polymer matrix gives a change from temperatures and still increase in absorbance or darken in light blue to various shades of dark blue. This change in color significantly on increasing the temperature. However, absorbance is presumed to be due to the increase in concen we have discovered several, nitrogen containing, ligands tration of the HeMLC's: Ni(1-EtBIMZ), Br, and/or Ni(1-Et 65 which do not participate well in a LeMLC. This effect is BIMZ).Br. Depending on the relative concentrations of illustrated by comparing FIGS. 29 and 30. In FIG. 29 the Ni(II), bromide and 1-EtBIMZ the presumed LETC reactions nitrogen containing ligand 6-methyl-2,2'-dipyridyl is US 7,525,717 B2 25 26 believed to participate in the LeMLC and give rise to the small In both bidentate cases, in this example, the coordination is but, troublesome absorbance between about 575 nm and 750 believed to be completed by two bromide ions. Thus the nm at 25 C. Addition of another methyl group to the ligand to spectra are consistent with (1) a dipyridyl amine with one give 6,6'-dimethyl-2,2'-dipyridyl decreases the absorbance methyl group-hindered pyridine and two bromides and (2) between 575 nm and 750 nm as shown in FIG. 30. This is two pyridines connected in ortho positions by an amine because the latter, nitrogen-containing ligand is more steri methylene bridge with the pyridine connected to the methyl cally challenged in trying to participate in the nominally ene group being methyl group hindered and two bromides. octahedral configuration, while it still participates nicely in The absorptions in FIG. 44 between about 400 nm and 450 the nominally tetrahedral configuration around nickel with nm are believed to be more likely due to the ortho-nitrogen two bromide ions. Other nitrogen containing ligands with this 10 affect disclosed above than to any tridentate character of the advantage include 6-methyl-N-(6-methylpyridin-2-yl)-N- 6-methyl-N-(6-methylpyridin-2-yl)methyl-N-pyridin-2- propylpyridin-2-amine, 6-butyl-6'-methyl-2,2'-bipyridine, ylpyridin-2-amine ligand. This example discloses a remark 2,2'-propane-2,2-diylbis(1,3-benzothiazole), 2,2'-propane-2, able LETC system in terms of a single system, with a single 2-diylbis(1-propyl-1H-benzimidazole), 2,2'-propane-2.2- ligand other than halide, with good gray appearance, a large diylbis(1-pentyl-1H-benzimidazole), several 6-alkylsubsti 15 change in visible light transmission and little color Sweep tuted dipyridylamines and to some extent most ortho throughout the temperature range of 25 to 105 C. For the substituted pyridines. spectra in FIG. 44 we calculate Y to be 82.8, 52.8, 21.4, 9.7 Many TC systems involving Ni(II), bromide and nitrogen and 6.2 at 25 C, 45C, 65C, 85C and 105 Crespectively. We based ligands have little absorbance between about 410 nm also calculate c to be 12.9, 17.9, 15.0, 9.7 and 5.7 at 25 C, 45 and 470 nm and thus they have a “valley” or a “well in the C, 65 C, 85C and 105 Crespectively. absorption spectra in this wavelength range even at elevated Multiple kinds of transition metal ions in the same LETC temperatures. This valley or well makes these systems diffi Solution or layer can give rise to at least two types of useful cult to use in combination with other systems to achieve gray behavior. One type is illustrated in FIG.3 in which ions of one appearance in multilayer systems unless the system with kind of metal are largely in a HeMLC throughout the tem which they are combined happens to absorb in the 410 nm to 25 perature range of interest and ions of the other kind of metal 470 nm region. A significant advantage is realized when there switch from largely being in a LeMLC at lower temperatures is at least Some increase in absorbance in this range as the to largely being in a HeMLC at a higher temperature. In FIG. temperature increases. As illustrated especially in Examples 3 it appears that the Co(II) has a higher affinity for iodide 18, 36 and 40 and the corresponding figures, there is a TC and/or a lower affinity for TMOLP as spectral peaks consis phenomenon that we call “well-filling’. In contrast, there are 30 tent with CoI remain at nearly constant magnitude many systems without well-filling as exemplified by throughout the 25 to 105 degree Celsius range. On the other Examples 7, 13, 19 and 22. While for Examples 18, 36 and 40 hand, the amount of Ni(II) coordinated by iodide appears to there is no absorption peak in the 410 nm to 470 nm region, at increase and the amount coordinated by TMOLP is believed least there is an increase in the absorbance in the valley or to decrease as the temperature increases. The spectral peak well. What the nitrogen based ligands, in each of these 35 with a at about 508 nm is consistent with a charge examples, have in common is a nitrogen as a heteroatom in a transfer peak in the visible for NiI. The system in FIG. 3 ring and they also have an amine nitrogen on a carbon alpha has significant advantages when used in Sunlight Responsive to the heteroatom nitrogen which is also the position on the Thermochromic, SRTTM, windows as the nearly temperature heterocyclic ring that is ortho to the heteroatom. Thus it is independent absorbance of CoI, is largely in the NIR and believed that this nitrogen attached to a position ortho to a 40 causes the system to warm on Sunlight exposure. The Sun heteroatom nitrogen, simply called the “ortho-nitrogen exposure induced temperature rise causes an increase in the affect, is responsible for the well-filling effect. The systems in concentration of NiI and a decrease in visible light trans Examples 18, 36 and 40 are easier to combine into multilayer, mission. Any other thermochromic layer in contact with a gray systems especially with other systems or layers that have layer containing this system would also increase in tempera peaks in the 550 nm to 650 nm region which wavelengths also 45 ture and broad visible light attenuation is possible just from need to be attenuated to give a gray appearance. direct Sunlight exposure. With regard to well filling, it is useful to have thermochro The other type of multiple metal ion system is shown in mic systems in which a HeMLC comprises chloride or bro FIG. 10. This is an example of systems where the temperature mide coordinated to Ni(II) along with another ligand such dependence for the formation of completely different com that the ratio of the HeMLCs maximum absorption coeffi 50 plexes, even involving different kinds of transition metalions, cient in the 475 nm to 550 nm range to the HeMLC's mini allows for the simultaneous formation of multiple HeMLC's mum absorption coefficient in the 425 nm to 475 nm range is of the different kinds of transition metals ions over the same less than 4 to 1. temperature range, in the same solution. Heating this system An interesting ligand and TC system is presented in FIG. causes an increase in concentration for two HeMLC's at the 44. Here the nitrogen containing ligand appears that it might 55 same time. These HeMLC's might be Co(glycerol)Cl. have the possibility of being tridentate. However the spectra and Cu(glycerol)Cl. The use of ZnCl2 in this system is of Ni(II) based systems with ligands that are believed to explained in the next paragraph. coordinate with three nitrogens plus one or two halides, like Disclosed herein is yet another new type of thermochromic examples 8 and 33, have a main absorption peak at wave reaction. Here, ligands may exchange between being coordi lengths between 430 nm and 460 nm. FIG. 44 shows an 60 nated or ligated to a first kind of metalion and being coordi example of systems that have spectra more consistent with the nated or ligated to a second kind of metalion. The second kind ligand acting as two different bidentate nitrogen based of metal ion is a transition metal ion that forms a HeMLC ligands. This is observed even when there is only one of this which includes a ligand previously associated with the first ligand molecule per Ni(II) ion present in the system. This is kind of metalion. For the purposes of the present application, believed to be due to the time dependent switching of the 65 the first kind of metal ions are called exchange metals. The coordination of these types of ligands between one type of exchange metal may be a transition metal or another kind of bidentate configuration and another bidentate configuration. metal. In “exchange metal TC systems, ligands which are US 7,525,717 B2 27 28 ligated or coordinated to one metal shift to being ligated or wherein X and y are numeric variables that designate the coordinated to another metal with changes in temperature. As number of LeLand HeL, respectively. In order for the absorp the ligands shift from one kind of metal to another kind there tion of the system to increase with increasing temperature the are changes in the light absorption of the system. This is equilibrium must shift to the right in equation (16) as the particularly effective when the MLC with one of the metals temperature increases. This would give a net increase in the has a significantly lower molar absorptivity than the MLC light energy absorbed since the e's for the complex Me(HeL), with another metal for the same type of ligands or set of are larger than the e's for the complex Me(LeL), at many ligands. Zn(II) ions work well in exchange metal TC systems wavelengths in the visible and/or NIR range for nearly all of as the MLC's of Zn(II) often absorb little or no visible light the systems disclosed herein. In order for the reaction to be and it has been discovered that the ligands in Zn(II) MLC's 10 reversible the reaction must shift back to the left the same readily shift to other metal ions such as Co(II), Ni(II) and amount as the temperature drops back to its original value. Cu(II) ions as the temperature of the system increases. The equilibrium constant for this reaction is given by: Exchange metals function in place of or are used in combi nation with LeL’s. K=(Me(HeL)|LeL)/(LMe(LeL). HeLP) (17) Another example of an exchange metal TC system is 15 where the brackets are used to signify concentration, (al shown in FIG. 11 for the proposed equilibria: though to be more accurate one could use activities). While the equilibrium constant is “constant at a given temperature (15) for wide variations in concentration, there is a different “con stant at each temperature. The temperature dependence of Once again the reversible, thermally induced shift in the the equilibrium constant is determined by the standard free equilibrium equation gives rise to a LETC process. In this energy change, AG, of the reaction, which in turn is deter case the chloride is still the HeL since it is the ligand in the mined by the standard enthalpy change, AH, of the reaction. HeMLC. In this case Y-BL is believed to play the role of the This can be seen from the following well known equations: LeL and the exchange metal ion is Zn(II). In the Solution of FIG. 10, Zn(II) is also used but this time it is in combination 25 AG=AH-TAS (18) with a LeL, glycerol, to allow the simultaneous formation of HeMLC's of two metals at once as described above. AG=-RTIn K. (19) Mn(II) is of particular interest as an exchange metal because even its tetrahedral MLCs have low molar absorp tion coefficients; see for example: F. A. Cotton et. al. J. Amer. 30 For most of the LETC systems we have discovered, AH of Chem. Soc. 84, 167-172 (1962). Exchange metal type LETC reaction is roughly constant over the temperature range of 0 to systems that have been demonstrated or should be considered 100 Celsius. If we assume the value of AH is actually con are based on Mn(II), Ni(II), Co(II), Sn(II), Cd(II), Cu(II), stant over the temperature range of interest, then the magni Al(III) and Sb(V). See Examples 179-188 and Table 12 for tude of the change of K, with temperature is dependent only more details. 35 on the magnitude of AH. Also, for the equilibrium to shift to LETC systems can be combined with essentially any other the right and for the net sunlight energy absorbed by the thermochromic phenomena. AVO or dopedVO film may be system to increase with a temperature increase, K must included on a substrate that is in contact with a LETC layer on increase. This can be seen from the mass balance in equation the other side of the substrate. Alternatively, we have discov (16) where the Me(HeL), must increase for the absorbance ered that certain thermochromic materials like ring opening 40 to increase. Given a constant total concentration of all the compounds are compatible with some LETC systems and ingredients used to make up the system, the only way for the remarkably they can even be incorporated into the same solu equilibrium to shift to the right is for the value of the equilib tion or layer. rium constant to increase; see equation (17). The value of K, FIG. 31 shows the thermochromic performance for a increases as the temperature increases only if AH is positive LETC system in combination with a compound known as 45 as shown in equation (20). The larger the positive value of Oxford Blue and FIG. 32 shows the thermochromic perfor AH for the equilibrium reaction the larger the increase in the mance for another LETC system in combination with a com value of K. Over a given temperature range, as shown by the pound known as Ruby Red. Both of these materials are ther following equations: mochromic based on a thermodynamic shift in the equilibrium between the ring-closed, colorless form and the 50 K(T,)=exp(-AH/RT)*exp(AS/R) (21) ring-opened, highly absorbing form. Ruby Red and Oxford Blue are available from James Robinson LTD of Hudders K(T,)=exp(-AH/RT,)*exp(AS/R) (22) field, England and they are also available from Keystone Aniline Corporation of Chicago, Ill. K(T)/K(T,)-exp((AH/R)*(1/T-1/T)) (23) 55 where T and T, are the high and low temperatures over Thermodynamics of Reversible Equilibria which the LETC system is being evaluated. Equation (23) is independent of AS and shows that the highest performance LETC processes involve reversible reactions in which the for a LETC system, in terms of the largest increase in light extent of the reaction, (or the position of the equilibrium), is 60 absorption, over a given temperature range, comes with the determined by the thermodynamic parameters of the reaction, highest positive value of AH. This is supported by the graph the temperature of the system and the total concentrations of each of the reactants/products in the system. One of the many in FIG. 47 which shows the increase in the ratio of equilib types of LETC reactions, which are governed by a reversible rium constant values for two different temperatures as a func thermodynamic equilibrium reaction, may be represented by tion of AH. This is simply a graph of equation (23) for T 65 equal 85 C and T, equal 25 C, however it is a powerful the following equation: illustration of the utility of having high AH for LETC reac Me(LeL), tyHeLMe(HeL)+xLeL (16) tions. US 7,525,717 B2 29 30 However, the larger the positive value of AH, at a given system with the following LETC equilibrium equation for a temperature and a given value of AS, the smaller the value of bidentate LeLand a monodentate HeL: K. It may be possible to have such a large positive value of Me(LeL)+4HeL Me(HeL)+3LeL (25) AH giving such a small value of K, that even a many fold increase in the value of K, gives little or no observable light 5 The system is assumed to have the following very realistic absorption change. This may happen because the Me(HeL), parameters: is so low that even a many fold increase in Me(HeL), with AH=50 kJ/mol temperature is still a Small concentration. Thus a large posi AS=110 J/mol:K tive value of AS is desirable, (if not necessary), in conjunc 10 e(Me(LeL))=1 l/mol cm at , of HeMLC tion with a large, positive AH if a reasonably low concentra e(Me(HeL))=280 l/mol cm at of HeMLC tion of materials or a reasonably small path length, (layer Layer Thickness=b=0.075 cm thickness), is to be used. In essence, the AS of the equilib rium reaction is important in that its value helps determine the Me=0.2M position of the equilibrium at each temperature, while AH Equation 25 is assumed to be the only equilibrium of inter determines the temperature dependence. FIG. 48 helps illus 15 est, which may be nearly the case for many of our systems, trate the influence of AS on the effective temperature range especially those in an indifferent or poorly coordinating Sol for absorbance changes for LETC reactions like: vent. Also assumed are (1) all of the metalions are present in the LeMLC=Me(LeL) or the HeMLC=Me(HeL); (2) all of Me(LeL),+4HeLMe(HeL)+3LeL (24) the HeL’s molecules are free in solution or part of the FIG. 48 shows the absorbance calculated for a wavelength HeMLC; and (3) all of the LeL’s molecules are free in solu where the only LeMLC=Me(LeL), has as e of 1 liters/ tion or part of the LeMLC. The thermochromic behavior in molecm at a max of the HeMLC and the only HeMLC=Me many of the figures herein shows these assumptions to be (HeL) has an e of 280 liters/molecm at a max of the reasonable. HeMLC. The absorbance is calculated as a function of tem For each ratio, R., of HeL/Me), the LeL was deter perature by first calculating an equilibrium constant at each 25 mined which would give the system an absorbance of A=0.8 temperature based on the AS values shown in FIG. 48 and a at 85C based on the above parameters, equilibrium equation AH of the reaction of 60 kJ/mol. Then the concentrations of and the equation: Me(LeL) and Me(HeL) at each temperature are calculated based on the equilibrium constant and the values: Me= (He L) (26) 0.2M. HeL=1.6M and LeL=2.5M. The concentrations 30 of Me(LeL) and Me(HeL), the values of the e's and a path The value of HeL is determined by the value of R being length of 0.075 cm are used to determine absorbance values. used and the specified Me. The LeL values that were FIG. 48 confirms that while the overall magnitude of the determined and then used are shown in FIG. 49. Using these absorbance change with temperature is determined by the LeLs, the absorbances at various temperatures throughout value AH, the temperature range where this absorbance 35 the 25 C to 85 C range were calculated for each ratio of change takes place is highly dependent on AS. FIG. 48 HeL/Me. Then the absorbances versus temperature illustrates how important it is to find reversible equilibria were plotted in FIG. 49. This graph shows that there is sig reactions not only with large positive values of AH, but also nificant improvement in absorbance change over this tem with appropriately large positive values of AS, if LETC perature range as the ratio of HeL/Me is increased even systems are to operate over especially useful temperature 40 though the required amount of LeL also increases. ranges like 0 C to 100 C. In many practical applications there is a desire to have a TC The present application discloses many LETC systems in layer as thin as possible. LETC systems with thicknesses in the range of 0.02 to 0.5 cm with reasonable to excellent which not only are there large positive values for AH and performance are disclosed herein. To achieve high perfor AS, these values are such that there is significant thermo 45 chromic activity over the OC to 100C temperature range. This mance in thin films a relatively high concentration of metal has been done by choosing systems which combine transition ions should be present. However, there is a trade-off between how high the metal ion concentration needs to be and the metal ions, HeL's, LeL's and solvent systems to give the desire for a large ratio of HeL to Me, especially when desirable values of AH and AS which allow for large absor solubility limits are taken into account. bance changes over a desirable temperature range. In general 50 a AH value from 40 kJ/mol to about 90 kJ/mol for the As discussed before, the theoretical minimum metal ion reversible LETC reaction is useful. In general it is also useful concentrations depend on (1) the desired level of absorbance that the value of AS' in J/mol K be such that when the value at an elevated temperature and a particular wavelength or in J/mol K is divided by the value of AH in kJ/mol, that the series of wavelengths, (2) the path length, (layer thickness), of quotient be between 1.5 and 3.5 even though the units of this 55 the LETC system and (3) the e of the HeMLC. If an absor quotient may not be meaningful. Thus e.g. if AH is 40kJ/mol bance of at least, A(TA), is desired at a higher temperature then it is desirable to have AS' between 60J/mol K and 140 of operation at Some A, then the minimum metalion concen J/mol K. Once the system, with its thermodynamics, is cho tration must be greater than or equal to ACT, w)/(e(HeMLC, sen, we have discovered how to optimize the system even w)*b); where b is the path length or layer thickness in centi further by judicious choices of concentrations and ratios for 60 meters. Practically, we have discovered that the preferred the constituents involved, especially for relatively thin layers minimum Me is 1.5 times the theoretical minimum. in polymers. This is illustrated in many of the examples and is By analogy to the previous analysis, the maximum Me, discussed further below. to be used is less than or equal to ACT, w)/(e(LeMLC, )*b). Good performance for a chosen LETC system comes when Thus useful transition metal ion concentrations are given by the ratio of the total concentration of all HeL's to the total 65 the following range: metalion concentration, HeL/Me, is as high as possible. This is illustrated in FIG. 49 with a calculation based on a (HeMLC, )* b)) (27) US 7,525,717 B2 31 32 where ACT, ) is the desired absorbance at at some lower systems, it becomes important to find highly soluble versions temperature, T, and ACT, ) is the desired absorbance at W of HeL’s. Fortunately, we have found that high, effective at Some higher temperature, T. concentrations of halides in polymer Systems may be Of course the total metal ion concentration, Me, is also achieved when ammonium and phosphonium cations that are constrained by the solubility limit of the LeMLC's and the tetrasubstituted are used. The Substituents on nitrogen or HeMLC's in the system over the temperature range of opera phosphorus may be alkyl, aryl or combinations thereof. tion as all of the Me in the system is either in LeMLC's or After consideration of Me, and HeL, comes LeL. In HeMLCs. The Me is also constrained by the ability of the fact, when high concentrations of Me, and HeLa are used, system to provide an adequate HeL. Thus the useful Me, the limitation on the practicality of the system may depend on is also determined by: 10 the solubility limit or physical properties imparted by the LeL(s). As long as the LeL is below its solubility limit and Mes().25*(solubility limit of HeL) (28) the limit where physical properties of the system become Reasonably good, although still approximate, values fore unacceptable, the specific LeLand its concentration are pref can be found with a known metal ion concentration and an erably chosen such that the absorbance of the LETC system, appropriate excess of LeL or HeL so that essentially all of the 15 (even when the system is a thin polymer layer), is less than 0.2 metal is converted to or is present in the LeMLC or the at 25 C while the absorbance still increases to greater than 0.8 HeMLC form. The measured absorbance divided by the path at 85 C. These absorbances are for the active wavelength length and the total metal ion concentration provides useful range of TC activity for the particular LETC system. These values of e(LeMLC) and of e(HeMLC). The following ranges of TC activity are illustrated in FIGS. 1-46 in liquid approximate e values, mostly in Y-BL, were determined by Solution with a large, (1 cm), path length. However, more Such a procedure and can be used to calculate maximum and remarkable are the results in FIGS. 51-58 for polymer layers minimum preferred Me in a variety of LETC systems since with thicknesses from 0.031 to 0.098 cm. Many more ranges the value of e for coordination compounds is not particularly of absorbance changes are given in Table 27. sensitive to the solvent involved: Thus, a high metalion concentration is desirable as long as 25 it is possible to still have large a ratio of HeL/Me, and a TABLE 2 concentration of LeL high enough to provide a desirable absorbance range. Another advantage of having large values LeMLC na(e) max(e) max(e) max(e) for HeLand LeL can be seen by considering the mass Ni(NPG)* 395(7) 660(3) 720(3) 1194(4) balance and equilibrium equations below. Ni(TMOLP)?" 383(6) 630(2) 711(2) 1097(3) 30 Ni(water)." 396(6) 661 (2) 726(3) 1163(3) Ni(DMSO).” 4.20(10) 695 (3) 784(3) 1177(3) Co(EG)* 518(9) K=(Me(HeL)/(LeLF)/(LMe(LeL), JFHeLP) (30) Co(Y-BL).’" 518(11) Co(PC).2* 516(10) If the HeLand LeL, are both large relative to Me. Co(18-crown-6)* 519(8) 35 then the concentrations of free, non-coordinated HeL and Co(bis(methylsulfinyl methane)* 546(8) LeL change only a small amount during a temperature , is a wavelength of maximum absorbance in nanometers induced shift in equilibrium. Small percentage changes in e is the molar absorption coefficient in liters (mole * cm) concentration of non-coordinated LeLand HeL during a tem perature induced shift in equilibrium corresponds with larger

TABLE 3 HeMLC na(e) max(e) na(e) max(e) sna (e) CoCl 635 (475) 670(660) 695(810) CoBr’ 642(235) 666(695) 700(1025) 724(1210) CoI2. 696(410) 724(775) 782(1930) Co(BusPO)* 560(205) 607(305) 634(360) Co(CFCOO) 535 (125) 572(175) Co(salicylate) 538(235) 577(360) Co((4-MeOPh)2PO) 561 (220) 590(295) 608(315) 639(360) NiCl2- 658(205) 704(210) NiBr? 709(285) 757(295) NiI2. 508(1650) 835(440) Ni(1-EtBIMZ).Br. 58O(220) Ni(1-EtBIMZ)Br, 640(255) Ni(4-(3-PhPr)Pyr).Br. 639(225) Ni(N Pr- 435 (155) 717(45) dipicolylamine)Br2 Ni(N-Bu-di(1-MeBIMZ- 448(140) 770(35) 2-yl-methyl)amine).Br. Ni(PhP).Br. 590(195) 911(250) 1139(50) Ni(PhP).I. 419 (4520) 498(1800) 561 (1730) 709(345) 747(410) Ni(TTCTD)2+ 500(370) is a wavelength of maximum absorbance in nanometers e is the molar absorption coefficient in liters (mole * cm)

65 Given the advantages of large ratios of HeL/Me, and changes in Me(HeL), and Me(LeL), than would be the desire for high Me, and the desire for thin layer LETC achieved otherwise. Thus when the ratio of HeL to metalion US 7,525,717 B2 33 34 is large and at the same time there is a large and appropriate removed as much a possible by pre-drying materials to be concentration of LeL one obtains the highest performance for processed, venting during extrusion and/or drying of the the system over a given temperature range. LETC layer prior to subsequent use. Also, it is possible to use “monomeric' LeL's that are diols, triols or polyols that have Polymers B-diol functionality wherein one or both of the hydroxy groups is a secondary or a tertiary alcohol which helps pre In LETC systems, polymers may provide a variety of func vent this “trans-acetalation of the cyclic acetal moieties from tions. They may serve as: the PVB to the other LeL's present. This is particularly impor a solvent or cosolvent tant when the other LeL is more effective than the PVB at an indifferent matrix for the rest of the system 10 providing LeL character since the trans-acetalation process the Solid phase of a gel may decrease the overall amount of LeL character in the some or all of the LeL character system. This is shown in the following undesirable reaction some or all of the HeL character scheme: a laminating material which may also provide shatter resis tance 15 TC or non-TC plastic substrates which may serve as win Scheme 1 dow panes separator layers barrier layers N^^^^^^- Sealants OH a combination of the above functions N. N. N. Polymers for TC Layers CHCH2CH3 CHCH2CH3 CHCH2CH3 PVB Sometimes polymer layers are referred to as films below a 25 certain thickness and are referred to as sheets above that thickness. The LETC layers of the present invention may be so films or sheets and may be free standing or Suspended as a separate layer. Alternatively, the layers may be placed on a N^^^^^^- substrate or between substrates or be used to laminate sub 30 strates together. Remarkably, our LETC reactions take place s OH OH s OH | in solid polymer based systems fast enough that there is CH2CH2CH CH2CH2CH essentially no lag time between the temperature change and the change in absorbance, at least on the time scale of 10 to 20 C seconds. 35 Polymers for LETC layers include: poly(vinylalcohol), H1 NCHCHCH, poly(vinyl butyral), poly(vinylethylene-co-vinylalcohol), CH2OH poly(vinylacetate), poly(N-vinylpyrrolidone), urethanes, hydroxyalkylcelluloses, hydroxy-Substituted acrylates and CHCH-C-CHOH their copolymers. Other polymer possibilities include: poly 40 (2-vinylpyridine), poly(1-glycerol methacrylate), cellulose CHOH carboxymethyl ether salt, cellulose hydroxyethyl ether, poly CH3CH CH-OH (2-ethyl-2-oxazoline), poly(hydroxyethyl methacrylate) and its copolymers, poly(vinyl methyl ether), polyacrylamide and poly(N,N-dimethylacrylamide). 45 HO + One of the polymers, poly(vinylbutyral), (PVB), is made O O in multiple steps. Generally, polyvinylacetate is hydrolyzed to remove most of the acetyl groups and form polyvinylalco NCHCH2CH3 hol. Then most of the alcohol or hydroxyl groups are reacted with butyraldehyde to forms cyclic acetal groups. The PVB 50 formed is thus a copolymer Sometimes referred to as: poly LETC layers, based on PVB as a polymer matrix, may be (vinylbutyral-co-vinylalcohol-co-vinylacetate). PVB for effectively mixed and extruded in one step using a twin screw many LETC systems has a high hydroxyl content and pro extrusion system. This avoids a separate, potential costly or vides substantial LeL character. The cyclic acetal portion of thermally damaging compounding step. The twin screw sys the PVB acts as a good and indifferent solvent for many of the 55 tem allows mixing and dissolution of the LETC material in other constituents of the LETC system. Preferred hydroxyl PVB and the use of a gear pump between the end of the content in this case is 18% or greater of that originally present extrusion barrel and a film forming die allows the production in the poly(vinyl alcohol). For a few LETC systems where of high quality films. The materials may be pre-dried and the little LeL character is required, as for example with iodide extruder may be vented to allow additional water and other and/or phosphine compounds as HeL's, PVB with lower 60 gases to be removed from the polymer prior to and during hydroxyl content is may be used. production of LETC layers. The materials that are fed into an PVB is a useful polymer since it is well suited for use in extruder may be purged with an inert gas like nitrogen or lamination of glass sheets. However, in the presence of water argon. However, a LETC layer in PVB may be produced and possible catalysts the acetal groups are subject to without the need for inert atmosphere conditions in the feed hydrolysis which would free butyraldehyde molecules. These 65 process as long as the extruder and die temperatures are kept molecules could subsequently react with monomeric LeL's below 150 C. The use of processing temperatures below 150 which are B-diols. In this case it is preferred that water be C is particularly advantageous in Systems where iodide and/or US 7,525,717 B2 35 36 phosphine compounds are used as HeL's to prevent irrevers The plasticizers may be any material known in the art of ible discoloration in the layer produced. Above this tempera plastics and polymer processing as a good plasticizer for the ture, the performance of the LETC layer produced may be particular polymer in which a LETC system is contained, as seriously compromised. long as the plasticizer does not seriously degrade the perfor mance or durability of the LETC system. For example, if the Substrates polymer is poly(vinylbutyral), conventional plasticizers are found in the art and include diesters of triethylene glycol, of A Substrate may serve as a mechanical Support for LETC tetraethylene glycol, of adipic acid or of phthalic acid. system or layers when they are not free standing by them Plasticizer character is also provided by materials not con selves. However, substrates are not considered part of the 10 ventionally used as plasticizers. Thus, diols and triols, in the LETC system unless the LETC system itself is a free standing amount normally used to provide LeL character, are effective plastic sheet. If a LETC system is soft and has little structural plasicizers. In addition, quaternary ammonium and quater integrity, it may simply be coated on a Substrate. Alterna nary phosphonium halides are also surprisingly good at plas tively, a pair of Substrates, generally each made out of the ticizing LETC polymer layers. These ligand-plasticizers are same material, may be laminated together with a LETC layer 15 effective in plasticizing poly(vinylbutyral) so that it is easier which comprises a polymer. Here the substrates provide to process into a film or sheet by extrusion at lower tempera mechanical Support and provide a symmetrical configuration tures and the films or sheets are easier to process further that is not prone to bowing on heating. Bowing is minimized especially when it comes to lamination of the LETC layer when the thermal expansion coefficients of the substrates are between sheets of glass or making a pre-laminate with a the same or closely matched. The laminate formed by two separator layer as described below. substrates bonded together with a LETC layer may act a Other unconventional plasticizers that not only help pro safety or impact resistant window pane. This is especially vide enhanced processing and desirable physical properties to valuable for bullet resistant and hurricane resistant window the LETC layers produced may also provide enhanced solu panes. In a laminate configuration the Substrates may act as bility for LETC system components. These unconventionally barriers to the ingress of oxygen, water and other contami 25 plasticizers include solvents like: acetonitrile, glutaronitrile, nates over the area of the LETC layer. To provide an overall 3-methoxypropionitrile, sulfolane, 1,1,3,3-tetramethylurea, barrier, the edges of the laminate may be sealed. dimethylsulfoxide, hexamethylphosphoramide, propylene Useful Substrates include plastics and glass. Useful plastics carbonate, Y-butyrolactone, 8-caprolactone and dimethylfor for use as Substrates include acrylic and polycarbonate sheets. mamide. Useful glass sheets are float glass or drawn sheets. Useful 30 While liquids may be used as plasticizers, we have found glass sheets for use as Substrates are ones that have been have that there are times when it is useful to have a plasticizer that been cut very cleanly or have edge treated by seaming, grind is a solid powder at room temperature. This allows the plas ing, mechanical or flame polishing and/or "pencil' edging so ticizer to be physically mixed into the polymer resin without they resist cracking when heated. Also useful are glass sheets causing the mixture to become sticky and difficult to feed which have been heat strengthened, heat tempered or chemi 35 from a feed hopper into the feed throat of an extruder. Par cally tempered so that they also resist cracking when heated, ticularly useful materials that act as plasticizers and are solids especially when non-uniformly heated. at room temperature are the LeL diols and triols which are An approach has been developed in which a PVB film is room temperature solids. Some of these with their melting bonded on one side of a tempered or heat strengthened sheet points are given below. of glass and a thin film of plastic film is bonded to the PVB to 40 provide a good optical quality Surface. Examples of the thin plastic films are polyester, poly(ester terephthalate), poly TABLE 4 (acrylic) or poly(carbonate). The thin plastic film may have an Plasticizer LeL m.p. “excited Surface or adhesion promoting coating on the side pentaerythritol 255-259 C. to be bonded to the PVB. Excited surfaces may be provided 45 2-(hydroxymethyl)-2-methylpropane-1,3- 200-2O3 C. by plasma, corona or OZone treatment. The thin plastic film diol may optionally be coated with a low emissivity or NIR reflec TMOLP 60-62 C. 2-(hydroxymethyl)-2-propylpropane-1,3- 100-102 C. tive coating on one or both of its surfaces. This structure was diol prepared with tempered glass and it withstood temperature cis,cis-1,3,5-cyclohexanetriol, dihydrate 113 C. ranges from -40 C to +100 C without warping, bowing or 50 NPG 124-130 C. delaminating. Even a thermo-shock test on going directly 2,2-dibutyl-1,3-butanediol 41-43 C. from a freezer at -40 C to +100 C did not cause breakage or 2,2-diethyl-1,3-butanediol 59-61. C. delamination. The combination of using tempered or heat 2-butyl-2-ethyl-1,3-propanediol 41-44 C. strengthened glass, PVB with good thermal expansion/con traction characteristics and a thin plastic film with an excited 55 Surface has allowed for this advantageous light weight, low Stabilizers and Additives and Barriers cost and highly durable structure. Stabilization of LETC systems involves preventing or Plasticizers minimizing degradation due to heat and/or light induced reac 60 tions of materials within the system or reactions with mate LETC systems, contained in polymers, benefit from the rials which come from the environment. Of course the best presence of plasticizers. The benefits include ease of process approach to stability is to find materials that are inherently ing in for example an extrusion process including lower extru high in stability and we have discovered numerous LETC sion temperature, lower torque and bettermixing. Plasticizers systems with good to excellent inherent stability including increase ease of product handling as the layers produced with 65 certain systems involving Ni(II) coordinate by iodide and plasticizers are easier to roll-up and process later in, for Ni(II) coordinated by iodide in combination with other example, a lamination process or a pre-lamination process. ligands. Somewhat less desirable than good inherent stability US 7,525,717 B2 37 38 is to provide barriers and seals against the ingress of things These short wavelength absorbing additives, not only pro that contribute to degradation, especially oxygen, water and mote stability as part of LETC system or layer, they can be ultraviolet light. This approach is discussed below with added to a polymer like PVB and extruded in a film with regard to barriers and in the section on seals. Even less desir excellent UV barrier properties. Barrier films with a cutoff of able, yet still an important approach, is to provide additives about 390 nm have been prepared with 0.5 weight % Tinu which help deal with degradation processes via competitive vin R. 326 in an approximately 500 micron thick layer of light absorption, tying up degradation products or inhibiting Butvar RB-90 which was plasticized with tri(ethylene glycol) further degradation. bis(2-ethylhexanoate). A cutoff of about 400 nm is obtained LETC systems described herein exhibit excellent inherent under similar conditions with 1 weight% Tinuvin R. 326 in a stability. Many of these systems have been exposed to tem 10 similar film. peratures of 80 C for more than 10,000 hours with little or no Any of the UV absorbing materials disclosed herein may degradation. Also, thermal stabilizers have been found which be used as shortwavelength absorbers in barrier layers, LETC are compatible with the LETC systems and provide enhanced layers, plastic Substrates and separator layers. However, some thermal stability. These include antioxidants and free radical of the second group UV stabilizer/absorber materials are inhibitors such as the hindered phenols. Some useful thermal 15 Somewhat effective at complexing to metal ions and these stabilizers include 2,6-di-tertbutyl-4-methylphenol, (BHT), complexes are not always stable with time. Therefore when IrganoxR 245, IrganoxR 1010, IrganoxR 1035, IrganoxR) materials from the second group are added directly to LETC 1076 and IrganoxR 5057. The IrganoxR) materials are avail systems or layers it is useful to choose the materials which are able from Ciba Specialty Chemicals Corporation of Tarry sterically hindered against strong complex formation or are town, N.Y. inherently poor complexing agents. The more useful materi Photodegradation, especially from short wavelength light, als from group two in this case are Tinuvin R. 213 Tinuvin R (like UV and short wavelength visible light), is an issue for 234 Tinuvin R. 326, Tinuvin R. 327, Tinuvin R 328, Tinuvin R many chromogenic systems including at least Some LETC 400, Tinuvin R 405 and Tinuvin R. 479. systems. Short wavelength light may be blocked by an FIG. 42 is a good illustration of the addition of UV 25 absorber/stabilizers directly to a LETC system. Here the absorbing barrier placed between a vulnerable layer and a Tinuvin R 405 does not appear to interfereby coordinating the source of UV and short wavelength visible light like the sun. Ni(II) ions. Also, FIG. 42 shows that the absorbance of the Multiple layers of LETC systems are used in some cases to system is very high at wavelength shorter than about 380 nm. achieve broad spectral coverage and a particular colorappear This system is thus a great barrier for any system that might be ance, especially a gray appearance. A highly advantageous 30 behind this system when it is exposed to Sunlight. configuration for the multilayer LETC systems is described Also effective in helping stabilize LETC systems and short below. This involves placing UV absorbing materials in a wavelength absorbing barriers are light stabilizers that them layer which itself is less vulnerable to photodegradation. This selves are not very effective at absorbing short wavelength layer is then placed between a source of short wavelength light. Preferred materials of this type are hindered amine light light and layers which are more Vulnerable to photodegrada 35 stabilizers, (HALS). Useful HALS include Tinuvin R) 144, tion. Other advantageous configurations involve a short Tinuvin R. 765 and Tinuvin R. 770 available from Ciba Spe wavelength light absorbing barrier being provided by a sub cialty Chemicals Corporation of Tarrytown, N.Y. strate layer or even by a separator layer placed between the The present application also discloses the use of the inher light source and the more Vulnerable layers. The advantages ent or the thermally induced short wavelength absorbing abil of these configurations should not be underestimated, espe 40 ity of LETC systems like those involving nickel ions and cially when one considers the difficulty in providing effective bromide ions. As seen in FIGS. 1 and 54, LETC systems like light absorbing barriers for most chromogenic systems. these provide outstanding absorption of short wavelength Short wavelength absorbing additives, sometime called light especially at higher temperatures. These LETC systems “UV absorbers”, may be divided into two groups. The first or layers may be used to protect layers that are more Vulner group includes materials which simply absorb short wave 45 able to combined thermal and photodegradation. Also some length light. Materials of this group are ethyl-2-cyano-3,3- of these layers with Ni(II) and bromide are inherently photo diphenylacrylate and (2-ethylhexyl)-3,3-diphenylacrylate stable on their own so they are better suited to being exposed available from BASF Corporation of Rensselaer, N.Y. as to Sunlight and acting as barriers in front of many other more Uvinul 3035 and Uvinul 3039 respectively. The second group UV sensitive LETC systems. involves absorbers of shortwavelength light which also func 50 UV barriers were found to be effective in extending the tion as stabilizers against the propagation of degradation ini useful life of LETC systems. In particular, when a thermo tiated by light exposure. Materials of this group are hydroxy chromic like that of FIG. 52 was laminated between pieces of benzophenones, hydroxyphenylbenzotriazoles and plain glass, the laminate had less than 2% haze as measured hydroxyphenyltriazines. Examples of these materials sold based on the amount of Scattering of transmitted light. After under the trade names: Tinuvin R. P. Tinuvin R. 213, Tinuvin R 55 500 hours of exposure to 0.55 watts per square meter at 340 234, Tinuvin R. 326, Tinuvin R327, Tinuvin R 328, Tinuvin R nm from a Xenon arc lamp in a chamber with a black panel 400, Tinuvin R 405 and Tinuvin R. 479. These materials are temperature of greater than 80 C, a gray hazy precipitate available from Ciba Specialty Chemicals Corporation of Tar formed gave the laminate a haze level over 10%. A laminate rytown, N.Y. Also useful are nickel salt stabilizers like dialky was prepared with three polymer layers between two sheets of ldithiocarbamates which are good UV absorbers even though 60 plain glass. The polymer layers were: 1) a UV barrier layer they are bit yellow in polymer films. containing Tinuvin R. 326 in PVB that cutoff wavelengths of Also useful are nickel salt stabilizers like bis(dialkyldithio light less than 390 nmi; 2) a poly(ester-terephthalate) separa carbamates)Ni(II) which are good UV absorbers even though tor; and 3) a layer of the same type of thermochromic system they are bit yellow in polymer films. While these materials as above. After this laminate was exposed with the UV barrier were generally considered to only be good absorbers, there is 65 facing the Xenon arc lamp, almost no gray hazy precipitate some literature to support the possibility that these material formed in the TC layer, the haze level was less than 5% and may also participate in stabilization by chemical means. the overall TC performance remained nearly unchanged. US 7,525,717 B2 39 40 Separators and Pre-Lamination meable in the process. Other adhesive systems include epoxies, silicones and acrylates. Separator layers may be desirable in multilayer thermo When multi-layer thermochromic systems are used or chromic systems to prevent intermixing of the thermochro when a separate UV barrier layer is used to protect a thermo mic materials. It is particularly useful for the separator layer chromic layer, it may be desirable to prepare a pre-laminate. to have an index of refraction close to that of the polymers This pre-laminate may be prepared by an in-line process by used in the thermochromic layer so that reflective losses will co-extruding the thermochromic layer(s), optional barrier be minimized. For example, poly(vinyl butyral) is an often layer and the separator layer(s) at the same time, and the used polymer for a LETC layer and it is reported to have an layers may be bonded together while the polymer layers are index of refraction from 1.485 to 1.490. When the LETC layer 10 still hot from the extruder dies. Alternatively, the layers may is contained in a layer of poly(vinylbutyral), plastic materials be extruded together in a multi-manifold die to produce a with good index of refraction match that may be used as barriers, TC layers and separator in an intimately bonded chemical separators or diffusion barrier layers between stack. LETC layers may be selected from the following Table: A pre-laminate may also be prepared in an off-line process 15 in which a barrier layer is bonded to one or more thermochro mic layers with one or more separator layers. Alternatively, TABLE 5 two or more thermochromic layers may be pre-laminated Refractive together with one or more separator layers in an off line Polymer index process. In the offline process, an advantage has been real Poly(4-methyl-1-pentene) 463 ized with the use of separator layers that have one or both of Poly(vinyl propionate) 466 their surfaces pretreated, activated or excited to promote Poly(vinyl acetate) 467 adhesion between the separator layer and the UV barrier Poly(vinyl methyl ether) 467 and/or thermochromic layers. The pre-laminates made with Poly(ethylene succinate) 474 Cellulose acetate butyrate 475 pretreated, activated or excited Surfaces on the separator layer Cellulose acetate 475 25 are easier to use in Subsequent lamination between sheets of Ethylene? vinyl acetate copolymer-40% vinyl acetate 476 glass or plastic since the layers stay together and behave Ethyl cellulose 479 essentially as a single layer. Pretreating, activating or exciting Poly(methyl acrylate) 479 Poly(oxymethylene) 480 the Surface dramatically decreases issues with de-lamination Ethylene? vinyl acetate copolymer-33% vinyl acetate 482 during years of use of LETC window panes. The separator Poly(n-butyl methacrylate) 483 30 Surfaces may be pretreated, activated or excited by glow Ethylene? vinyl acetate copolymer-28% vinyl acetate 485 Poly(methyl methacrylate) 489 discharge, plasma or corona treatment process in vacuum, Polypropylene, isotactic 490 inert atmosphere or in air. Alternately, pretreatment with Methyl cellulose 497 oZone may be provided in an oxygen atmosphere. Poly(vinyl alcohol) SOO Although, a separator or diffusion barrier layer is primarily Poly(vinyl methyl ketone) SOO 35 Poly(ethylene glycol dimethacrylate) SO6 used to prevent intermixing of the materials from individual Poly(isobutylene) S10 thermochromic layers when there are multiple thermochro Polyethylene, low density S10 mic layers present, they may also act as barriers to UV light. This allows the separator to protect underlying layers from UV exposure. Also, UV absorbing materials, like those Other, useful separators include polycarbonates, poly(ester 40 described in the additives section of this patent, may be more terephthalates) and other polyesters, especially those poly compatible with the separator layer than a layer containing a carbonates and polyesters that are hydrophobic or poor at LETC system. This is especially true given that some UV solubilizing salts. In addition, crosslinked or highly crystal absorbers/stabilizers like hydroxyphenylbenzotriazoles may line materials may be used as separators or diffusion barriers. have undesirable interactions with transition metal ions. For example poly(vinyl alcohol) is reasonably hydrophilic 45 Also, the separator may contribute to the structural integ but in the absence of water it is a good barrier because of a rity and shatter resistance of the window. In this case the high degree of order due to strong hydrogen bonding. separator function may be provided by a relatively thick film Crosslinking in a separator in general may also be effective in or sheet of plastic. With multiple thermochromic layers and the prevention of diffusion or migration of non-ionic ligands one or more, thick separator layers the overall window lami like pyridines, imidazoles and phosphines. Alternatively, 50 nate may even become hurricane, explosion, theft, vandalism non-ionic ligands may be attached to a polymer in the LETC and/or bullet resistant. layer or may be modified with the attachment of polar or ionic Substituents so they are less likely to diffuse through a sepa Seals rator. For example 1-hydroxyethybenzimidazole and a benz imidazole Substituted with a quaternary ammonium group are 55 Seals are of interest especially for LETC layers which are less likely to diffuse through a hydrophobic, polymeric, sepa sensitive to oxygen, water and/or environmental contami rator layer than an alkyl substituted benzimidazole like 1-Et nants. For example, Systems involving iodide, systems BIMZ. involving phosphine compounds and systems involving both An alternative type of separator may be provided by a iodide and phosphine compounds benefit from seals that thermoset type of adhesive that is used to bond multiple 60 minimize the ingress of oxygen in the layers containing these LETC layers together. The adhesive forming system may systems. An edge seal may be provided when the LETC layer contain reactive groups which optionally form bonds directly is laminated between sheets of glass or sheets of plastic. The to a polymer in the LETC layer. For example the adhesive edge seal should cover the edge of the laminate around the may contain isocyanate groups which are part of a polyure entire perimeter to provide a barrier for ingress of materials thane adhesive which covalently bond also to hydroxyl 65 into the LETC layer. The edge seal may be a thermoplastic, a groups of a hydroxyl group containing polymer on the Surface thermoset, a rubber, a metallized tape or combinations of a LETC layer and make the surface of the layer less per thereof. Useful thermoset seal materials are urethanes and US 7,525,717 B2 41 42 epoxies. Suitable seals are epoxy systems disclosed for use as required the more complicated and expensive the product perimeter seals in U.S. Pat. No. 6,665,107, the contents of becomes. Thus the systems that provide broad spectral which are hereby incorporated by reference. Useful thermo attenuation and gray appearance with one or at most two plastic Seal materials are good barrier polymers like poly layers are special. (vinyl alcohol), poly(vinylidene chloride), (polyvinylidene fluoride), EVOH, and certain rubbers. Thermoplastic or ther Applications moset systems overlayed with an impermeable metal foil or tape are useful edge seal systems especially when the LETC A preferable use for our LETC layers is as part of an SRTTM systems contain ligands like iodide orphosphine compounds window package. Many configurations are possible for Such they are or are not used as ligands. 10 windows. A few configurations are: 1) A LETC layer that is laminated between sheets oftem Color and Color Coordinates pered or heat strengthened glass, wherein this laminate serves as the center pane of a triple pane window. Pref See “Principles of Color Technology, 2" Edition”, F. W. erably, in this configuration, there is one or more than Billmeyer Jr. and M. Saltzman, John Wiley and Sons, Inc. 15 one low-e coating between the LETC layer and the inte (1981) for a discussion of color and color coordinates includ rior of the vehicle or building in which the window is ing definitions ofY, L*, a, b and c'. The variation ofc with installed. temperature is herein referred to as the color sweep or shift of 2) A LETC system is contained in a free standing plastic the LETC system. Generally, it is useful to have small varia sheet or is contained in a polymer layer which is lami tions in c i.e. small color sweep or shifts with temperature. nated between two plastic sheets and is used as the center Many useful systems or combinations of systems have both pane of a triple pane window. The interior pane of the Small c values and Small amount of color Sweep as discussed triple pane window preferably has a low-e coating on the below. surface facing the LETC system. For the use of LETC systems in applications like energy 3) A LETC layer is laminated between sheets of edge saving windows, especially, SRTM Windows, there is a 25 treated glass and is used as the exterior pane of a double demand for certain colors. While fixed tint windows which pane window. Either one or both of the glass surfaces in are gray, green, blue and bronze are in widespread use, the contact with the gas space of the double pane has a low-e most desirable color, (or lack thereof), for variable tint win coating. dows is gray. This is especially true when the window is or is 4) A LETC layer is bonded to a sheet of tempered or heat able to become heavily tinted as the view through a heavily 30 strengthened glass and a layer of plastic film is bonded to tinted gray window maintains the same color rendition for the LETC layer. This pane is used as the exterior pane of objects viewed through the window as is maintained with a a double pane window with the plastic film in contact lightly tinted or nearly colorless window. Also it is highly with the gas space or this pane is used as the center pane desirable for the daylighting that comes in through the win of a triple pane window. A pane with a low-elayer is used dow to be color neutral so that people and objects illuminated 35 by that light have a normal appearance. Disclosed herein are as the interior pane in either case and the low-e layer is interesting systems with a green, blue or bronze appearance oriented to face the pane with the LETC layer. when lightly tinted which change to gray when heavily tinted. 5) A LETC layer is laminated between a sheet of NIR These systems and those that are close to gray at all tint levels absorbing glass and the uncoated side of a sheet of glass are particularly useful. 40 coated with a low emissivity coating, which coating has LETC systems with absorbance peaks throughout the vis substantial NIR absorption character. This laminate is ible and/or NIR are disclosed herein. However, just a few used as the exterior pane of a double pane window with special, single composition systems that are reasonably gray the low emissivity coating in contact with the gas space have been found. A few more combinations of two composi of the double pane window. tions or layers of LETC materials have been discovered that 45 6) A LETC layer that is laminated between a first sheet of provide good gray appearance throughout the entire tempera tempered or heat strengthened glass and the uncoated ture range of intended use. Many more combinations involv side of a second sheet of tempered or heat strengthened ing three compositions or layers have been discovered that glass coated with a hard coat low emissivity coating. provide good gray appearance. Gray systems are illustrated in This laminate is used as the interior pane of a double the Examples Section of this disclosure. 50 pane window, wherein the hard coatlow emissivity coat Useful LETC systems are those that not only maintain a ing is in contact with the interior of the vehicle or build consistent gray appearance throughout a large temperature ing in which the window is installed. range; they also have a large change in visible light and/or Many more examples are given in our co-pending applica total solar absorption. Single layer LETC systems are dis tion on window structures. closed herein, which have a c of less than 25 throughout the 55 SRTTM windows may be used in a variety of applications temperature range of 25 C to 85C and still have a change in such as variable light absorption windows for residential and Y from greater than 70 at 25C to less than 15 at 85 C. Some commercial buildings including skylights and atrium glazing of the two layer LETC systems have a c of less than 21 and variable light absorption windows for boats, ships, air throughout the temperature range of 25 to 85C and still have craft and motor vehicles including moon roofs and Sun roofs. a change in Y from greater than 75 at 25C to less than 15 at 85 60 The windows may include artful designs of different colored C. Some of the three layer LETC systems have a c of less LETC systems like a variable light transmission stained glass than 15 and still have a change in Y from greater than 80 at 25 window. C to less than 15 at 85 C. These systems have minimal color When a triple pane window is constructed with the LETC shift over the active range of these novel TC systems. system as part of the center pane, there are two interfaces in Some of the multilayer systems have the added advantage 65 contact with a gas for each pane, giving a total of six inter that they also provide reversibly variable transmission in the faces. The reflection from each of these interfaces will add up NIR as well as the visible. However, the more compositions and may become objectionable. Thus we have discovered an US 7,525,717 B2 43 44 advantage to placing anti-reflection coating on one or more Surfaces in the window package. TABLE 6 LETC systems may be used to prepare variable reflectance mirrors by placing LETC layer on a reflector or on a substrate Conc. coated with a reflector. The LETC layer may be protected by Type Materials in LETC System (molarity) laminating the layer between a transparent Substrate and a Example 1 - FIG. 1 reflector coated substrate. The reflector may be used as a TBABr resistive heater to heat the LETC layer and thus vary the TMOLP reflectance of the mirrors. Ni(CIO)2–6H2O LETC systems may be used as a means to monitor the 10 Example 2 - FIG. 2 temperature in various environments as long as the transmis TEAC-HO sion change of the system can be measured or observed. TMOLP Temperature determination may range from visual compari Ni(CIO)2–6H2O Sons to full spectral measurements. This is a particularly Example 3 - FIG. 3 useful means of monitoring temperature at the tip of a fiber 15 optic cable that may be used for, among other things, as a catheter for insertion into a body. An SRTTM window may be used to monitor the intensity and directness of Sunlight, as both the transmission and the Example 4 - FIG. 4 temperature of the thermochromic layer change with Sunlight TBAI intensity in a reproducible manner. CFCOOLi LETC systems may be used to display information in TMOLP devices where certain regions are heated or the active LETC Co(BF)—6H2O layer is patterned in a manner Such that individual segments Example 5 - FIG. 5 may be heated. Heating may be provided by resistive heating 25 TBABr O.12 or by selective light exposure by a light Source Such as a laser 2,2'-ethane-1,2-diyldipyridine O.04 or other source providing a focused light beam or localized NPG 2.05 heating. O.04 While our best understanding of these TC processes Example 6 - FIG. 6 involves changes in concentrations of MLC's, we have dis 30 LiBir PhP covered and herein describe many thermochromic systems TMOLP 1.27 that have a reversible, net increase in their abilities to absorb Co(BF)—6H2O O.O1 light energy in the visible and/or NIR range as the tempera Example 7 - FIG. 7 ture of the system is increased, no matter what the explana tion. 35 TEAC HO PhP EXAMPLES Example 8 - FIG. 8

Table 6 gives the formulations of liquid solution LETC TBABr systems for Examples 1-46. In each case, the solution was 40 N-Bu-di(1-MeBIMZ-2-yl-methyl)amine prepared by dissolving the materials in 5 milliliters of Y-BL. TMOLP In each example, Some of the Solution was placed in a 1 cm borosilicate cuvette, a small stir bar was placed in the cuvette Example 9 - FIG.9 and the cuvette was placed in the sample beam of a Shimadzu TBAI UV-3101 PC spectrophotometer. The solution was stirred and 45 PhP heated and the temperature was monitored with a thermo couple immersed in the Solution in the cuvette. A similar, unheated 1 cm cuvette containing only the solvent was placed Example 10 - FIG. 10 in the reference beam of the spectrophotometer. In each ZnCl2 example the absorption spectrum of the Solution was mea 50 TEAC HO sured from 350 nm to 1150 nm at 25C and then the solution Glycerol Metal Cu(NO)—2.5H2O was heated to 45 C and the spectrum was measured. Then the Metal Co(BF)—6H2O solution was heated to 65 C and the spectrum was measured Example 11 - FIG. 11 and so on at 85C and 105 C. FIGS. 1-46 correspond, numeri cally, to Examples 1-46. The Figures show the spectrum 55 EXM ZnCl2 measured at 25 C, at 45C, at 65 C, at 85 Cand at 105 C for the HeL TEAC H2O (TEACI) Solutions described in these Examples. In each case the spec Metal Cu(NO)—2.5H2O trum with the lowest absorbance corresponds to 25C, the next Example 12 - FIG. 12 highest absorbance spectrum corresponds to 45 C and so on HeL TTCTD Such that the spectrum with highest absorbance peaks in each 60 LeL 2-methyl-1,3-propanediol Figure corresponds that measured at 105 C. In all the FIGS. Metal Ni(CIO)2–6H2O 1-46, the X axis, (horizontal axis), gives the wavelengths in Example 13 - FIG. 13 nanometers and the y axis, (vertical axis), gives the absor HeL TBABr bance values. For the examples in Table 6, the molarity values HeL 2,2'-propane-2,2-diylbis(1-propyl-1H-benzimazole) were calculated based on an assumed 5 ml total Solution 65 LeL Volume. Volume changes due to components dissolved in the Metal 5 ml of Y-BL were not considered.

US 7,525,717 B2

TABLE 6-continued TABLE 6-continued

Conc. C Materials in LETC System (molarity) OlC. Type Materials in LETC System (molarity) NPG O.61 Ni(CIO)2–6H2O O.O2 Example 46 - FIG. 46 Example 39 - FIG. 39 o TBABr O.1 HeL potassium hydrotris(3,5-dimethylpyrazol-1-yl)borate O.OOS N.N.N',N'-tetramethyl-1,3-propanediamine O.O2 10 HeL TBABr O.O26 N: O)—6H2O LeL TMOLP O.O26 412 V112 Example 40 - FIG. 40 Metal Ni (CIO)2–6H2O O.OOS

TBABr O.1 N-pyridin-2-ylpyridin-2-amine O.OO8 15 Nyl-N-pyridine-ylmethylpyridin-2-amine 9. Examples of Gray Combinations Ni(CIO)—6H2O O.O2 Example 41 - FIG. 41 Some of the single layer LETC systems we have discov TBABr O.2 2O ered, which have a c of less than 25 throughout the range of N-pyridin-2-yl-N-(pyridin-2-ylmethyl)pyridin-2- O.04 25 C to 85 C with a Y from greater than 70 at 25 C and less y O.O89 than 15 at 85 Care listed in Table 7. These are c and Y values Ni(CIO)2–6H2O O.O2 for the LETC system alone and not for other components like Example 42 - FIG. 42. Substrates that might be part of a window package. Each TBA oooo 25 example in Table 7 is based on a formulation given by the 4-(3-PhPr)Pyr O.OO3 entry from Table 27. The spectra used to calculate c and Y is TMOLP O.O14 the given percentage of the spectra obtained when heating a PhP(TBA).NiI O.OO3O.OO1 solution of the formulation- given- in- Table 27. LETC systems with the characteristic given in Table 7 can beachieved either Tinuwin (R) 405 0.003 30 by using the percentage of the formulation from Table 27 or Example 43 - FIG. 43 by keeping the formulation the same and changing the path TBAB O.1 length or layer thickness of the system. It is also possible to HeL 2-pyridin-2-ylethanamine O.O2 achieve similar results with these systems for a wide variety LeL NPG O.74 35 of concentrations and path lengths. Thus information from Metal Ni(CIO)—6H2O O.O2 liquid solution based LETC systems with large path lengths oExample 44 - FIG. 44 can be used to design thinner polymer layer based systems HeL TBABr O.1 with similar change in white light transmission, similar colors and similar color sweep or shift with temperature.

TABLE 7 % of Entry 25 C. 45 C. 65 C. 85 C. Example # of Table 27 Yakbic: Ya's bic: Ya's bic: Ya's bic: 47 80% of 925 75.6-10.6-4.711.6 60.0-2.9-2.03.5 33.911.9-2.212.1. 14.922.3-7.223.4 48 105% of 708 74.8-18.3-4.618.8 61.6-15.9-8.217.9 36.4-9.3-14.417.2 14.9-0.1-16.016.0 49 89% of 733 72.3|-18.31418.4 59.2-14.14.414.8 34.8-4.35.97.3 14.7|4.83.96.2 50 82% of 827 73.2-10.4-6.412.3 57.0-9.0-7.6.11.8 32.8-3.9-9.19.9 14.7|44-405.9 51 78% of 830 75.4-9.3-4.710.4 56.7-7.8-6.810.4 30.9-4.0-9.910.7 14.8-1.5-3.63.9 52 80% of 829 76.1-7.7-3.68.5 56.4-4.1-9.2|10.0 31.13.1-16.917.1 14.99.1-15.818.2

For examples of two layer systems, the spectra in FIGS. TABLE 6-continued 1-32, were combined in various combinations and each com 55 bination was checked to see if it met certain performance Conc. criteria with regard to color and range of transmission. Com Materials in LETC System (molarity) binations made by adding various amounts of the spectra HeL 6-methyl-N-(6-methylpyridin-2-yl)methyl-N- O.O2 from just two LETC layers are given below. These combina pyridin-2-ylpyridin-2-amine tions met the criteria of c less than 20 throughout the range LeL NPG 1.21 60 of 25 C to 85 C with a Y from greater than 75 at 25 Candless Metal Ni(CIO)2–6H2O O.O2 than 15 at 85 C. These are values for the LETC system alone Example 45 - FIG. 45. and not for other components like Substrates that might be HeL TBABr O.1 part of a window package. In practice one can reliably predict HeL N-(6-methylpyridin-2-ylmethyl)pyridin-2-amine O.O2 the combined spectrum of two or more systems by simply LeL NPG 1.49 65 adding the spectra of two separate systems at each tempera Metal Ni(CIO)2–6H2O O.O2 ture of interest. Since the TC systems are, or would be in separate layers, it is not surprising that the absorption spectra US 7,525,717 B2 49 50 of light passing through the layers would be a simple Sum of tance, Y, and the color coordinates, (see Principles of Color the separate absorption spectra. From the Summed absorption Technology, 2'' Edition”, F. W. Billmeyer Jr. and M. Saltz spectra one can calculate the overall white light transmit- man, John Wiley and Sons, Inc. (1981)).

TABLE 8

% of % of 25 C. 45 C. 65 C. 85 C. Ex. # Figure Figure Ya' bic:* Ya's bic: Ya's bic: Ya's bic: 53 66% of 2 86% of 12 873-103.13.3 70.05.95.37.9 38.311.53.212.O 14.714.0-2.814.3 54 32% of 3 56% of 20 89.6-4.79.610.7 72.8-6.62.57.1 38.3-44-11.612.4 14.75.5-13.7|14.8 55 60% of 4 54% of 1284.3-1.28.08.0 65.01.23.94.1 35.45.6-4.37.O 14810.5-10.614.9 56 24% of 5 28% of 27 91.2-4.55.57.1 70.8-2.46.46.9 37.45.12.25.6 14613.8-O.2138 57 28% of 5 16% of 31 88.8-7.58.811.5 69.2-8.211.414.0 36.9-5.813.714.9 14.54.0|10.211.0 58 34% of 5 62% of 33 78.8-7.86.210.0 60.8-10.99.814.6 33.0-8.80.88.9 15.0-3.1-12.713.1 59 36% of 5 10% of 23 90.7-8.58.411.9 69.1-10.19.614.0 35.7-10.34.8|114 14.7-4.0-9.7|10.4 60 38% of 5 34% of 9 90.4-8.08.611.8 68.5-8.98.312.2 35.3-5.7-3.06.4 14.8-0.9-14.214.3

For examples of three layer systems, the spectra in FIGS. 1-46, were combined in various combinations and the com binations were checked to see if they met certain performance criteria with regard to color and range of transmission. Many combinations gave good values for Y and c when adding various amounts of the spectra from three LETC layers. Some representative results made are given below. These combina 25 tions met the criteria of c less than 10 throughout the range of 25C to 85 C with a Y from greater than 80 at 25 Candless than 15 at 85 C. These are values for the LETC system alone and not for other components like Substrates that might be part of window package.

TABLE 9

% of % of % of 25 C. 45 C. 65 C. 85 C. Ex... ii Figure Figure Figure Ylabic:* Ya's bic: Ya's bic: Ya's bic: 61 10% o 25% of S 30% of 27 90.2-5.35.97.9 68.7-366.67.6 34.52.7183.3 2.49.6-129.7 62 10% o 20% of 26 35% of 27 89.8-23-0.52.3 66.70.2-434.3 33.24-88.9 4.27.5-0.17.5 63 15% o 100% of 6 95% of 12 803-2.23.74.3 59.8-2.81.934 32.531.83.5 4.1933.29.8 64 20% o 35% of 4 60% of 36 85.6-4.289 63.90|7|7 32.16.92.47.3 4.784-479.6 65 25% o 65% of 2 80% of 12 86.4-2.73.34.3 69.12.44.65.2 37.75.71.25.8 4.582-5.59.9 66 25% o 30% of 36 60% of 41 82.6-0.7-182 66.9-0.1-0.505 3631-1735 4.66.2-7.79.9 67 30% o 65% of 44 40% of 46 81.5-6.84.98.4 582-438.79.7 28.52.599.3 4.36.26.89.2 68 35% o 30% of 12 65% of 41 81.60.5-3.43.5 67.60.5-2.72.7 37.92.2-3.44.1 4.46.9-7.210 69 45% o 15% of 23 85% of 39 822-281.53.2 63.80.81.718 36.41.87.88 4.88.60.48.6 70 45% o 50% of 39 50% of 45 84.6-4.93.96.3 65-18727.4 35.139.4|9.9 4.37.14.98.7 71 50% o 90% of 12 100% of 24 82.80.53.33.3 63.32.43.24 34.24.72.25.2 4.79.139.6 72 S5% o 15% of 7 65% of 36 86.1-6.9518.6 63.7-2.455.5 31:45.81.66 4785-49.5 73 S5% o 60% of 9 90% of 39 81-231.93 62.51.90.82 35.85.80.SS-8 479.20.39.2 74 S5% o 30% of 14 70% of 36 87.4-6.86.79.5 66-1.8969.8 33.14.28.79.7 4.83.123.7 75 95% o 15% of 13 65% of 36 834-6. 65.38.5 62.2-0.76.66.6 3185.69.7 4.59.41.395 76 95% o 10% of 28 65% of 36 82.1-5.43.86.6 60.80.544.1 318.3.2.78.7 59.3-1.494 77 95% o 5% of 32 65% of 36 81.7-55.67.5 60.3-0.57.17.1 30.75.76.58.7 486.32.86.9 78 95% o 65% of 36 15% of 37 82.7-7.85.39.4 61.7-2.16.66.9 30.76.95.28.6 49.60.19.6 79 100% o 5% of 19 70% of 36 84.7-7.96.19.9 634-2.57.98.3 325.97.79.7 4.97.63.78.4 8O 20% of 2 65% of 37 30% of 45 804-5.94.27.3 64.2-2.37.57.9 34.54.87.58.9 4.89439.9 81 25% of 2 15% of 23 85% of 39 83.6-1.5.1.52.1 65.32.81.93.4 3737.48 4.68.7-28.9 82 25% of 2 35% of 36 50% of 41 84.1-1-0.6.1.2, 67.90.3O80.8 35.924-152.8 4.53.6-9.19.8 83 25% of 2 55% of 39 45% of 45 85.6-3.13.34.S 66.21.15.65.7 35.65.75.68 4.19.1-139.2 84 30% of 2 60% of 9 90% of 39 82.6-0.622.1 64.34.41.14.5 36.57.6-0.27.6 4.59.7-2.29.9 85 30% of 2 45% of 18 20% of 27 81.8-7.9-18 66.4-4835.6 37O6.46.4 4.43.27.98.5 86 30% of 2 25% of 27 50% of 37 83.2-3.82.84.7 67.9-0.6444.4 37.64.93.86.2 58.93.39.5 87 35% of 2 10% of 7 70% of 36 87.8-5547.4 6S.S.O.96.76.7 31.88.23.68.9 48.5-3.59.2 88 35% of 2 35% of 12 45% of 44 86.4-445.26.8 642-199.59.7 32.50.79.910 4.62.26.36.7 89 35% of 2 75% of 12 30% of 16 87.1-5.34.97.2 68.7-3.58.28.9 37.2-2.99.510 4.5-1788.1 90 45% of 2 15% of 31 40% of 43 83-543.26.2 64.404383.8 34.82.97.783 4.73.97.98.8 91 45% of 2 10% of 32 55% of 36 81.60.5545.4 60.75.26.88.6 31743.88.3 454.1-2.95.1 92 45% of 2 35% of 36 40% of 40 834-6.1648.9 611.19.99.9 30.64.26.98.1 4.6-0.7-2.12.2 93 50% of 2 10% of 13 65% of 36 873-45.36.7 66.82.27.47.7 33.38489.4 4.86.1-2.76.7 94 50% of 2 10% of 19 65% of 36 87.9-56.38 67.21.38.58.6 33.57.45.99.5 4.46.4-26.7 95 70% of 2 80% of 12 5% of 45 872-183.64 69.73.96.67.6 37.676.29.4 4.27.81.88 96 75% of 2 5% of 9 80% of 12 873-193.64 70.23.466.9 38.45.947.2 4.66.9-1.67.1 97 75% of 2 5% of 11 80% of 12 86.8-2.84.755 69.82.67.47.9 38.15.74.77.4 457.5-2.37.9 98 80% of 2 70% of 12 5% of 31 86.7-3.14.SS.4 69.90.27.77.7 37.9-1.19.69.7 4.1-0.855.1

US 7,525,717 B2

TABLE 9-continued

% of % of % of 25 C. 45 C. 65 C. 85 C. Ex. ii Figure Figure Figure Ylable Ya's bic: Ya's bic: Ya's bic: 175 15% of 9 80% of 13 40% of 16 80.2-4.95.57.4 62.1-4.55.36.9 31.9-3.11.23.3 15-7.3|-1.47.5 176 15% of 9 5% of 24 95% of 41 80.32.2-5.35.7 68.4-2.9-2.94.1 39.3-9.3|-1.39.4 14.9-8.6-4.19.5

For Examples 177 and 178, the molarity values were cal 10 Table 12. For examples 179 to 188, the molarity values were culated based on an assumed 5 ml total Solution Volume. calculated based on an assumed 5 ml total Solution Volume. Volume changes due to components dissolved in the 5 ml of Volume changes due to components dissolved in the 5 ml of solvent were not considered. solvent were not considered. Each solution was cycled back and forth between hot and Example 177 15 cold several times and the amount of TC activity remained consistent. On cooling the Solution decreased back to its A solution was prepared which was 0.004M FeBr, and original color and appearance and the absorbance decreased 6.39Mwater in Y-BL. The solution was placed in a cuvette and back to its original level. the absorption spectra were measured at various temperatures against a cuvette containing only Y-BL. The absorbance val Example 179 ues at several values of W. and temperatures values are given below: A dark blue Solution was prepared in Y-BL containing 0.01M Co(BF):6HO and 0.15M tri-n-butylphosphine TABLE 10 oxide. Making the solution 0.039M in Zn(CFSO) caused it 25 to change to light purple. On heating, the solution turned max 25 C. 45 C. 65 C. 85 C. progressively darker blue. 470 O.71 1.25 2.72 S.OO 606 O.09 O.10 O.13 O.12 Example 180 712 O.O3 O.O3 O.O6 O.O6 780 O.O2 O.O3 O.OS O.O7 30 A green solution was prepared in propylene carbonate containing 0.01M Co(BF):6H2O and 0.34MNaI. Making the solution 0.113M in Zn(CFSO), caused it to change to Example 178 nearly colorless. On heating, the Solution turned progres sively darker green. A significant portion of the change in A solution was prepared which was 0.004M FeBr, 6.4M 35 absorbance of this system takes place in the near infrared. water and 0.02M di(pentaerythritol) in Y-BL. The solution was placed in a cuvette and the absorption spectra were mea Example 181 Sured at various temperatures against a cuvette containing only Y-BL. The absorbance values at several values of A purple solution was prepared in Y-BL containing 0.01M and temperatures values are given below: 40 Co(BF):6H2O and 0.032M 2,2'-ethane-1,2-diylbis(1-ben Zyl-1H-benzimidazole). Making the solution 0.016M in TABLE 11 Zn(CFSO) caused it to change to light purple. On heating, the solution turned progressively darker purple. max 25 C. 45 C. 65 C. 85 C. 45 402 O.88 1.37 2.87 S.OO Example 182 471 O.29 O.80 2.32 S.OO 607 O.04 O.04 O.04 O.O7 A dark blue Solution was prepared in Y-BL containing 0.01M Co(BF):6H2O and 0.10M tetrabutylammonium Examples 177 and 178 disclose systems which show an 50 thiocyanate. Making the solution 0.044M in Zn(CFSO), interesting case for thermochromic activity with Fe(II) going caused it to change to light purple. On heating, the Solution to what is believed to be the HeMLC form FeBr, on heat turned blue and became progressively darker blue. ing. Exchange Metal Examples 179 to 188: In each case the Example 183 Solution was prepared by dissolving the materials in 5 milli 55 liters of the solvent listed. Some of the solution was placed in A dark blue Solution was prepared in Y-BL containing a 1 cm borosilicate cuvette, a small stir bar was placed in the 0.01M CoBr, and 0.064M TBA (4-MeOPh)PO). Making cuvette and the cuvette was placed in the sample beam of a the solution 0.036M in Zn(CFSO), caused it to change to Shimadzu UV-3101 PC spectrophotometer. light purple. On heating, the solution turned blue and became The solution was stirred and heated and the temperature 60 progressively darker blue. was monitored with athermocouple immersed in the Solution in the cuvette. A similar, unheated 1 cm cuvette containing Example 184 only the solvent was placed in the reference beam of the spectrophotometer. The absorbance, A., at a lower tempera A dark red solution was prepared in Y-BL containing ture, T, and the absorbance, A. at a higher temperature, T, 65 0.002M NiI and 0.12MNaI. Making the solution 0.037M in for various wavelengths of maximum absorbance, W., are Zn(CFSO) caused it to change to light yellow. On heating, given for Examples 179 to 188 involving exchange metals in the solution turned progressively darker orange-red. On cool US 7,525,717 B2 55 56 ing the solution changed back to its original light yellow After the solvent was removed, another sheet of glass was appearance and the absorbance decreased back to its original pressed onto the layer to give a layer thickness of 0.043 cm. level. Example 190 Example 185 A LETC layer of poly(vinyl alcohol-co-ethylene), (con A bright green solution was prepared in Y-BL containing tent: 27 mole% ethylene), containing 0.2 molal NiBr:XHO, 0.0012.5M Cu(NO):2.5H2O, 0.006M Co(BF):6HO and 2.0 molal TBABr, 0.2 molal 4-(3-PhPr)Pyr and 1.0 molal 0.095M TEACl:HO. Addition of some ZnC1, caused the TMOLP was solvent cast from 50% water-50% n-propanol solution to change to dark blue green. Further addition of 10 onto a sheet of glass. After the solvent was removed, another ZnCl until the solution was 0.145M in ZnCl2 caused the sheet of glass was pressed onto the layer to give a layer Solution to turn very lighttan. On heating, the solution turned thickness of 0.078 cm. progressively darker bluegreen. Example 191 Example 186 15 A LETC system in a urethane layer was prepared by mix A blue solution was prepared in Y-BL containing 0.022M ing 28.9 wt % molten TMOLP 7.2 wt % g-BL 14.5 wt % Ni(NO):6HO and 0.18M TEACl:HO. Making the solu diethyleneglycol and 49.4 wt % Bayer Desmodur R N-3200 tion 0.1M in MnCl2 caused it to change to light green. On to give a isocyanate to hydroxyl ratio of 0.3 to 1. This poly heating, the solution turned progressively darker green and urethane forming solvent system was made 0.12 molal in the absorbance, in a 1 cm cuvette, increased at certain wave CoBrand 0.47 molal in LiBr. The layer was allowed to cure lengths and decreased at another wavelength as shown in between sheets of glass to give a layer thickness of 0.078 cm. Table 12. Example 192 Example 187 25 A LETC system in a urethane layer was prepared by mix A blue solution was prepared in Y-BL containing 0.02M ing 31.2 wt % molten TMOLP 15.6 wt % diethyleneglycol Ni(CIO):6HO and 0.20 MTBABr. Making the solution and 53.2 wt % Bayer DesmodurRN-3200 to give a isocyan 0.19MinMnBr, causedit to change to yellow. On heating, the ate to hydroxyl ratio of 0.3 to 1. This polyurethane forming Solution turned green and became progressively darker green. 30 solvent system was made 0.06 molal in CoBrand 0.50 molal in LiBr. The layer was allowed to cure between sheets of glass Example 188 to give a layer thickness of 0.075 cm. A light red solution was prepared in Y-BL containing 0.01 Example 193 M Cu(NO):2.5H2O, 0.09 M TEACl:HO and 0.32 M ZnCl2. On heating, the solution turned progressively darker 35 A LETC system in a urethane layer was prepared by mix red. ing 42.8 wt % molten TMOLP and 57.2 wt % Bayer Desmo

TABLE 12

EXM Example WIALITIAir ITH WIALITIAir Tir WalALTLIAH TH 179 5480.17250.6685 5860-17250.8785 6350.15251.0185 18O 3830.93255.0185 7450.28253.0785 181 5280.32250.6385 5610.41250.8985 5970.26250.6685 182 5640.10|250.2785 6200.112250.4885 6400..102250.4885 183 533|O.19250.4985 5890.2O250.7385 641|0.25250.9885 184 517|O.O9251.0O85 724|O.O1250.1485 185 4750.22250.8785 5850.09325|0.6185 68.0.0.166251.1085 186 4440.68250.4985 6190.25251.085 7050.34250.83|85 187 47O157251518.5 649|O.34251.7585 7190.28250.9985 188 47OO.22251.3485 8530.72250.7685

A variety of polymers may be used as part of LETC system. dur(R) N-3200 to givea isocyanate to hydroxyl ratio of 0.33 to The use of several of these polymers to make films that were 55 1. This polyurethane forming solvent system was made 0.11 then used to make laminates is described in the following molal in CoBr, 0.46 molal in LiBrand 0.23 molal N-propyl examples. The absorbances at several temperature for the 2,2'-dipyridylamine. The layer was allowed to cure between laminated made from the systems of Examples 189-214 are sheets of glass to give a layer thickness of 0.090 cm. shown in Table 13. 60 Example 194 Example 189 A LETC system in a urethane layer was prepared by mix A LETC layer of cellulose acetate butyrate, (M. c.a. 200, ing 32.1 wt % moltenTMOLP, 16.0 wt %y-BL and 51.9 wt % 000; content: 17% butyryl, 29.5% acetyl, 1.5% hydroxyl), 65 Bayer DesmodurR N-3200 to give a isocyanate to hydroxyl containing 0.1 molal CoCl2, 2.6 molal LiCl and 3.2 molal ratio of 0.4 to 1. This polyurethane forming solvent system ZnCl2 was solvent cast from 2-butanone onto a sheet of glass. was made 0.13 molal in NiBr:XHO and 0.92 molal in US 7,525,717 B2 57 58 TBABr. The layer was allowed to cure between sheets of glass 0.44 molal N. Pr-DPamine and 0.50 molal TMOLP was to give a layer thickness of 0.075 cm. Solvent cast from n-propanol onto a sheet of glass. After the Solvent was removed, another sheet of glass was pressed onto Example 195 the layer to give a layer thickness of 0.053 cm. A LETC system in a urethane layer was prepared by mix Example 202 ing 33.9 wt % molten TMOLP, 11.3 wt % dimethylphthalate and 54.8 wt % Bayer DesmodurRN-3200 to give a isocyan A LETC layer of hydroxypropylcellulose, (M. c.a. ate to hydroxyl ratio of 0.4 to 1. This polyurethane forming 80,000), containing 0.40 molal NiBr:XHO, 2.0 molal solvent system was made 0.10 molal in NiCl:6H2O, 0.65 10 TBABr, 1.2 molal 1-MeBIMZ and 1.75 molal TMOLP was molal in TBAC1 and 0.18 molal 4-tert-butylpyridine. The Solvent cast from n-propanol onto a sheet of glass. After the layer was allowed to cure between sheets of glass to give a Solvent was removed, another sheet of glass was pressed onto layer thickness of 0.075 cm. the layer to give a layer thickness of 0.058 cm. Example 196 Example 203 15 A LETC system in a urethane layer was prepared by mix A LETC layer of hydroxypropylcellulose, (M. c.a. ing 27.2 wt % molten TMOLP, 6.8 wt % dimethylphthalate 80,000), containing 0.07 molal NiI:6HO, 1.0 molal LiI, and 66.0 wt % Bayer DesmodurRN-3200 to give a isocyan 0.35 molal PhP and 0.7 molalTMOLP was solvent cast from ate to hydroxyl ratio of 0.6 to 1. This polyurethane forming n-propanol onto a sheet of glass. After the solvent was solvent system was made 0.11 molal in Ni(NO):6H2O, 1.10 removed, another sheet of glass was pressed onto the layer to molal in TBAI and 0.11 molal 4-tert-butylpyridine. The layer give a layer thickness of 0.050 cm. was allowed to cure between sheets of glass to give a layer thickness of 0.075 cm. Example 204 Example 197 25 A LETC layer of poly(methyl methacrylate), (M. 996, 000), containing 0.10 molal Ni(NO):6H2O and 2.0 molal A LETC system in a urethane layer was prepared by mix TBAI was solvent cast from 2-butanone onto a sheet of glass. ing 28.4 wt % moltenTMOLP 14.2 wt %y-BL and 57.4 wt % After the solvent was removed, another sheet of glass was Bayer DesmodurR N-3200 to give a isocyanate to hydroxyl pressed onto the layer to give a layer thickness of 0.030 cm. ratio of 0.5 to 1. This polyurethane forming solvent system 30 Example 205 was made 0.25 molal in NiBrixHO, 0.82 molal in TBABr and 0.51 molal 2-(2-dimethylaminoethyl)pyridine. The layer A LETC layer of linear poly(2-vinylpyridine), (M. ca. was allowed to cure between sheets of glass to give a layer thickness of 0.075 cm. 40,000), containing 0.60 molal Ni(NO):6H2O, 4.0 molal 35 LiBrand 4.0 molal TMOLP was solvent cast from ethanol Example 198 onto a sheet of glass. After the solvent was removed, another sheet of glass was pressed onto the layer to give a layer A LETC system in a urethane layer was prepared by mix thickness of 0.048 cm. ing 27.2 wt % molten TMOLP, 6.8 wt % dimethylphthalate Example 206 and 66.0 wt % Bayer DesmodurRN-3200 to give a isocyan 40 ate to hydroxyl ratio of 0.6 to 1. This polyurethane forming A LETC layer of poly(vinyl acetate), (M. ca. 167,000), solvent system was made 0.11 molalinNi(NO):6HO, 0.03 containing 0.40 molal Ni(NO):6H2O, 4.0 molal LiBrand molal Co(NO):6H2O and 1.10 molal in TBAI. The layer 3.0 molalTMOLP was solvent cast from ethanol onto a sheet was allowed to cure between sheets of glass to give a layer of glass. After the solvent was removed, another sheet of glass thickness of 0.063 cm. 45 was pressed onto the layer to give a layer thickness of 0.060 Example 199 C. Example 207 A LETC layer of hydroxypropylcellulose, (M. c.a. 80,000), containing 0.10 molal CoBr, 2.0 molal LiBr, 0.22 50 A LETC layer of poly(vinyl alcohol), (M13,000-23,000; molal N. Pr-DPamine and 4.0 molal TMOLP was solvent 87-89% hydrolyzed), containing 0.40 molal Ni(NO):6HO, cast from n-propanol onto a sheet of glass. After the solvent 4.0 molal LiBrand 3.0 molalTMOLP was solvent cast from was removed, another sheet of glass was pressed onto the water onto a sheet of glass. After the solvent was removed, layer to give a layer thickness of 0.048 cm. another sheet of glass was pressed onto the layer to give a Example 200 55 layer thickness of 0.055 cm. Example 208 A LETC layer of hydroxypropylcellulose, (M. c.a. 80,000), containing 0.10 molal NiBr:XHO, 4.0 molal LiBr A LETC layer of poly(vinyl alcohol), (M. 13,000-23,000; and 2.0 molalTMOLP was solvent cast from n-propanol onto 87-89% hydrolyzed), containing 0.20 molal CoBrand 0.81 a sheet of glass. After the solvent was removed, another sheet 60 molal LiBr was solvent cast from water onto a sheet of glass. of glass was pressed onto the layer to give a layer thickness of After the solvent was removed, another sheet of glass was O.053 cm. pressed onto the layer to give a layer thickness of 0.060 cm. Example 201 Example 209 65 A LETC layer of hydroxypropylcellulose, (M. c.a. A LETC layer of poly(vinyl alcohol), (M13,000-23,000; 80,000), containing 0.40 molal NiBr:XHO, 4.0 molal LiBr, 87-89% hydrolyzed), containing 0.20 molal CoBr, 0.81 US 7,525,717 B2 59 60 molal LiBrand 1.0 molal NPG was solvent cast from water onto a sheet of glass. After the solvent was removed, another onto a sheet of glass. After the Solvent was removed, another sheet of glass was pressed onto the layer to give a layer sheet of glass was pressed onto the layer to give a layer thickness of 0.050 cm. thickness of 0.078 cm. TABLE 13 Example 210 Absorbance Values as a Function of Temperature at a , in nm A LETC layer of poly(vinyl alcohol), (M. 13,000-23,000; 87-89% hydrolyzed), containing 0.20 molal CoBr, 0.81 Ex. ii max 25 C. 45 C. 65 C. 85 C. 10 molal LiBr and 1.0 molal 1,3-butanediol was solvent cast 189 671 O.O6 O.11 O.2O O4O from water onto a sheet of glass. After the solvent was 190 633 O16 O.38 0.73 23 removed, another sheet of glass was pressed onto the layer to 191 700 O.70 1.57 2.38 3.17 give a layer thickness of 0.078 cm. 192 700 O.38 122 2.04 2.73 193 638 O.04 O.20 0.55 .12 Example 211 15 194 698 O.10 O.34 O.71 17 195 555 O.04 O.20 O.36 O.82 196 524 O.04 O.S2 1.46 2.81 A LETC layer of poly(vinyl alcohol), (M. 13,000-23,000; 197 526 O.O3 O.14 O.39 O.71 87-89% hydrolyzed), containing 0.40 molal NiBr:XHO, 4.0 198 SO8 O.O2 O.15 O.S3 66 molal TBABrand 0.5 molal 1,3-butanediol was solvent cast 782 1.60 1.90 1.96 2.10 from water onto a sheet of glass. After the solvent was 199 642 O.08 O.31 O.64 O1 removed, another sheet of glass was pressed onto the layer to 200 700 O.17 O.39 O.83 36 give a layer thickness of 0.088 cm. 2O1 498 O.11 O.47 O.77 O3 2O2 600 O.15 O.49 1.02 49 Example 212 2O3 S61 O.17 O.32 O.67 .33 25 204 SO6 O.13 O.33 O.96 .98 205 552 O.11 O.24 O43 O.6O A LETC layer of poly(vinyl alcohol), (M. 13,000-23,000; 2O6 698 O.13 O.28 O.S2 O.96 87-89% hydrolyzed), containing 0.40 molal NiCl:6H2O and 2O7 665 O.10 O.25 0.55 O.88 4.0 molalcholine chloride was solvent cast from water onto a 208 702 O.65 O.66 1.OO 87 sheet of glass. After the solvent was removed, another sheet of 30 209 701 O.30 O41 O.87 73 glass was pressed onto the layer to give a layer thickness of 210 701 O.31 0.44 1.19 90 0.088 cm. 211 705 0.11 0.37 O.73 1.20 212 653 O.26 O.64 1.35 2.08 Example 213 213 642 O.17 O.48 1.12 62 214 703 O.13 O.28 O.S6 O.84 35 A LETC layer of poly(N-vinylpyrrolidone), (M. ca. 55,000), containing 0.20 molal CoBr, 2.0 molal LiBr, 2.0 molal N-propyl-2,2'-dipyridylamine and 4.0 molal TMOLP Examples of various LETC system prepared by solvent was solvent cast from ethanol onto a sheet of glass. After the casting with various types of PVB are given in Table 14. The Solvent was removed, another sheet of glass was pressed onto 40 Butvar Rand SolutiaR) type PVBs are available from Solutia the layer to give a layer thickness of 0.053 cm. Incorporated of Saint Louis, Mo. The CCP B-1776 is avail able from Chang Chun Petrochemical Co. Ltd. of Taipei, Example 214 Taiwan. The Aldrich PVB is available from Aldrich Chemical Company of Milwaukee, Wis. The numbers in front of the A LETC layer of poly(N-vinylpyrrolidone), (M. ca. materials in the table are molal concentration with the PVB 55,000), containing 0.40 molal Ni(NO):6H2O, 4.0 molal being the main solvent in each case. Satisfactory to excellent LiBrand 2.0 molal TMOLP was solvent cast from ethanol LETC layers were obtained with these various samples.

TABLE 1.4 Hydroxyl Ex. ii Metal Salt HeL(1) HeL(2) LeL(1) PVB Type Content 2.02m 1.75m Butwar (RB-72, 17.5-20.0% TBABr TMOLP Wt 216 2.02m 1.75m Butwar (RB-74 17.5-20.0% TBABr TMOLP Wt 217 2.02m 1.75m Butwar (RB-76 11.0-13.0% TBABr TMOLP Wt 218 2.02m 1.75m Butwar (RB-79 10.5-13.0% TBABr TMOLP Wt 219 2.02m 1.75m Butwar (RB-90 18.0-20.0% TBABr TMOLP Wt 220 2.02m 1.75m Butwar (RB-98. 18.0-20.0% TBABr TMOLP Wt 221 O.7m TBAI O2m 0.4m TMOLP Solutia (R) RA- NAA PPh3 41 222 O.7m TBAI O2m 0.4m TMOLP Solutia (R) NA PPh3 DM1 US 7,525,717 B2 61 62

TABLE 14-continued Hydroxyl Ex. ii Metal Salt HeL(1) HeL(2) LeL(1) PVB Type Content 223 0.07m NiI2. Butwar (R) NA xH2O SBTG 224 0.07m NiI2. CCPB-1776 NA xH2O 225 0.07m NiI2. Aldrich NA xH2O 18,2567

Examples 226 to 278 in Table 15 involve extrusion with vacuum bag. All of the laminates showed good thermochro various LETC systems which comprise Butvar R B-90 as mic activity when heated by various means and good dura solid polymer solvent. Extrusions were made with a Bra 15 bility when exposed to Sunlight, especially those containing bender conical twin screw extruder with counter rotating stabilizer additives. When films were extruded from formu screws. In example 263 the powders were first extruded as rope and the rope was chopped into pellets. The pellets were lations, where the metalions were added as a complex, it was fed back into the extruder and a very uniform film was pro easier to maintain constant feed of the powders into the duced for thickness or gage and for uniformity of composi extruder and there was an improvement in the uniformity of tion and coloration, i.e. uniform optical density when heated the extruded film. Laminates that were prepared from films as part of a laminate between sheets of glass. Laminates were made from powders dried before feeding into the extruder, made, from each film placed between two pieces of plain (see Notes in Table 15), showed improved performance and glass, in a heated platen press or by heating in a heated had better durability during Sunlight exposure.

TABLE 1.5 Extruder Examples Metal Ex. # Salt Complex HeL HeL LeL Additive(s)* Note 226 0.20m NiBr, 2.0m O50m xH-0 TBABr TMOLP 227 0.07m NiI2 xHO 0.7m TBAI 0.35m PhP 0.40m TMOLP 228 0.07m NiI2 xH2O O.75m TBA 229 0.20m NiBr, .0m 0.60m 1- 25m xH2O TBABr MeBIMZ TMOLP 230 0.07m NiI, xHO .75m TBA 231 0.20m CoBr, 0.81m LiBir 2.09m. TMOLP 232 0.07m Co(NO), O.70m 0.70m PhP On TMOLP 6H2O TBA 233 0.20m NiBr, .60m 0.40m 1- O50m xH2O TBABr MeBIMZ TMOLP 234 0.10m CoBr, .60m .75n TBABr TMOLP 235 0.20m NiBr, .60m 0.40m 1- 3.S.On NPG xH2O TBABr MeBIMZ 236 0.20m NiBr, .60m 0.40m 1- 3.On NPG dried xH2O TBABr MeBIMZ 237 0.20m NiBr, .60m 0.40m 1- 3.22 NPG xH2O TBABr MeBIMZ 238 0.07m NiBr, 0.7m TBAI 0.35m PhP 0.40m xH2O TMOLP 239 0.20m NiBr, O.60m 0.40m 1- 1.93m NPG xH-0 TBABr EtBIMZ 240 0.10m NiBr, .60m 0.40m 1- 2.5m NPG xH2O TBABr EtBIMZ 241 0.10m NiBr, .80m 0.80m PhP 0.80m xH2O TBABr TMOLP 242 O.O7m 70m 0.20m PhP 0.40m NiI2(PhP), TBA TMOLP 243 0.17m Ni(1- .60m 0.06m 1- 1.93m NPG EtBIMZ).Br. TBABr EtBIMZ 244 0.07m 70m 0.20m PhP 2.5m NPG NiI2(PhP) TBA 245 0.10m CoBr, .60m 2.25m 0.50% Tinuwin TBABr TMOLP 326 246 0.20m NiBr, .0m 1.00m xH2O TBABr TMOLP

US 7,525,717 B2 65 66 FIGS. 51 to 57 relate to Examples 279 to 285. The figures A piece of this film that was 0.098 centimeters thick was used show the spectra measured at 25 C, 45C, 65C and 85 C with to laminate two sheets of plain float glass together. The lami an Ocean Optics 2000 diode array spectrometer. For each nate was lightgreen and changed to light blue on heating. The spectrum in FIGS. 51 to 58, the absorbance spectrum of a spectrum of the laminate was measured at 25 C, 45C, 65 C reference sample, made with the same type offloat glass and 5 and 85 C. By subtracting out a reference sample, the spectral a plain piece of PVB film, was subtracted out. Thus the data for the film alone were calculated and plotted in FIG. 54. spectral data are for the LETC films alone. In each case the spectrum with the lowest absorbance corresponds to 25C, the Example 283 next highest absorbance spectrum corresponds to 45 C and so on Such that the spectrum with highest absorbance peaks in 10 A multilayer laminate was made with a 350 micron thick each figure corresponds to that measured at 85 C. In all the layer similar to the material of example 279 and a 460 micron FIGS. 51 to 58, the X axis, (horizontal axis), gives the wave thick layer similar to the material of example 280. Prior to lengths in nanometers and they axis, (vertical axis), gives the lamination, a 100 micron film of poly(esterterephthalate) was absorbance values. placed between the PVB films and the 3 layers of film stack 15 was laminated between 2 sheets of plain float glass. The Example 279 spectrum of the laminate was measured at 25 C, 45C, 65 C and 85 C. By subtracting out a reference sample, the spectral A physically blended mixture of powders was made by data for the film stack alone were calculated and plotted in stirring 38 grams of Ni(PPh.)I, 165 grams of TBAI, 4.4 FIG.55. The values of L*, a, b and Y for films making up grams of Tinuvin R) 144, 33 grams of PPhs and 34 grams of the laminate are given in the Table 16 at various temperatures. TMOLP into 633 grams of PVB, (Butvar R B-90). This mix ture was extruded to give a LETC film which varied from TABLE 16 about 0.03 microns to about 0.09 centimeters thick. A piece of this film that was 0.031 centimeters thick was used to lami Temperature (C. nate two sheets of plain float glass together. The laminate was 25 25 C. 45 C. 65 C. 85 C. very lighttan in color and changed to dark red on heating. The Y 91.5 79.7 45.6 12.4 spectrum of the laminate was measured at 25 C, 45C, 65 C a: -4.1 -4.0 -2.5 1.9 and 85 C. By subtracting out a reference sample, the spectral b: 4.0 S.6 8.4 12.3 data for the film alone were calculated and plotted in FIG. 51. c:* 5.7 6.8 8.8 12.5 30 Example 280 Example 284 A physically blended mixture of powders was made by stirring 71.5 grams of Ni(1-EtBIMZ).Br. 139.5 grams of A multilayer laminate was made with a 350 micron thick TBABr, 5.0 grams of Tinuvin R 405 and 144 grams of NPG 35 layer similar to the material of example 279, a 520 micron into 715 grams of PVB, (Butvar R B-90). This mixture was thick layer similar to the material of example 280 and a 220 extruded to give a LETC film which varied from about 0.04 to micron thick layer similar to the material of example 281. about 0.09 centimeters thick. A piece of this film that was Prior to lamination, 200 micron thick films of poly(ester 0.060 centimeters thick was used to laminate two sheets of terephthalate) were place between the films of PVB and the 5 plain float glass together. The laminate was lightblue in color 40 layers of film stack was laminated between 2 sheets of plain and changed to dark blue on heating. The spectrum of the float glass. The spectrum of the laminate was measured at 25 laminate was measured at 25 C, 45 C, 65 C and 85 C. By C, 45C, 65 Cand 85 C. By subtracting out a reference sample, Subtracting out a reference sample, the spectral data for the the spectral data for the film stack alone were calculated and film alone were calculated and plotted in FIG. 52. plotted in FIG. 56. The values of L*, a, b and Y for films 45 making up the laminate are given in the Table 17 at various Example 281 temperatures. A physically blended mixture of powders was made by stirring 6.99 grams of CoBr, 60.1 grams of TBABrand 73.6 TABLE 17 grams of TMOLP into 313.0grams of PVB powder, (Butvar(R) 50 Temperature (C. B-90). This mixture was extruded to give a LETC film which varied from about 0.04 to about 0.09 centimeters thick. A 25 C. 45 C. 65 C. 85 C. piece of this film that was 0.054 centimeters thick was used to Y 82.8 66.O 29.0 5.3 laminate two sheets of plain float glass together. The laminate a: -50 -6.6 -7.9 -6.7 was nearly colorless and changed to lightblue on heating. The 55 b: 5.2 6.O 6.1 7.2 spectrum of the laminate was measured at 25 C, 45C, 65 C c:* 7.2 8.9 1O.O 9.8 and 85 C. By subtracting out a reference sample, the spectral data for the film alone were calculated and plotted in FIG. 53. Example 285 Example 282 60 A multilayer laminate was made with a 430 micron thick A physically blended mixture of powders was made by layer similar to the material of example 279, a 300 micron stirring 33.0 grams of NiBrxHO, 388.1 grams of TBABr, thick layer similar to the material of example 280 and a 590 5.7 grams of Tinuvin R. 326, 5.7 grams of Tinuvin R) 144 and micron thick layer of the material from example 282. Prior to 100.9 grams of TMOLP into 600.7 grams of PVB powder, 65 lamination, 200 micron thick films of polycarbonate were (Butvar R B-90). This mixture was extruded to give film place between the films of PVB and the 5 layers offilm stack which varied from about 0.04 to about 0.11 centimeters thick. was laminated between 2 sheets of plain float glass. The US 7,525,717 B2 67 68 spectrum of the laminate was measured at 25 C, 45C, 65 C 0.07 m. NiI(PhP), and 85 C. By subtracting out a reference sample, the spectral O.7 m TBAI data for the film stack alone were calculated and plotted in FIG. 57. The values of L*, a, b and Y for films making up 0.2 m PhP the laminate are given in the Table 18 at various temperatures. 5 O4 m. TMOLP 0.49 wt % Tinuvin(R) 144 TABLE 18 in ButVar(R) B-90 PVB Temperature (C. The layers were treated as described below and the dura 10 bility of the laminates was tested for long term exposure at 80 25 C. 45 C. 65 C. 85 C. C. Tables 19 to 25 give the measured absorbance values at 25 Y 85.9 S8.1 25.4 5.8 Cand 85C at 425 nm and 565 nm as a function of time for the a: -8.0 -8.5 -8.6 -5.2 b: 6.3 6.9 5.7 8.7 laminate of the LETC layer in an 80 Coven in the dark. c:* 10.2 11.O 10.3 10.1 15 Example 287

Example 286 The LETC layer was exposed to room humidity for 24 hours and then was laminated between two pieces of glass and Three laminates were prepared by laminating a film stack the edge was sealed with epoxy. The absorbance data in Table like that disclosed in Example 285, except that poly(ester 19 show a significant increase in the absorbances at both terephthalate) film was used for the separators. These lami wavelength and both measured temperatures as a result of nates were used as the center panes of a triple pane insulated heat exposure. glass units. The insulated glass units were each placed on a box to simulate a vertically glazed, window unit in a building. 25 TABLE 19 In each window unit, the pane that was closest to the interior of the box had a Solarban(R) 60, low-e coating on the surface Absorbance that faced the center pane, thermochromic laminate. Solar Hours Absorbance Absorbance Absorbance 565 ban R. 60 is available from PPG of Pittsburgh, Pa. The exterior at 80 C. 425 nm 25 C. 425 nm.85 C. S65 mm 25 C. nm.85 C. pane in each case was clear, i.e. plain glass. The air space 30 O O.10 1.17 O.O6 0.57 between the exterior pane and the thermochromic laminate 409 O.19 2.06 O.08 1.03 was 0.38 inches and the air space between the thermochromic 1035 O.38 2.68 O.14 1.36 laminate and low-e coated pane was 0.5 inches. 2591 O.80 2.70 O.25 1.38 The window units were placed outdoors and exposed to Sunlight. One of the window units was oriented to face east, 35 one faced south and the third faced west. During the day the directness of sunlight on each window varied with the time of Example 288 day as the earth rotated. The east facing window was observed to tint to a dark gray appearance in the morning, the South facing window tinted dark gray in during midday and west 40 A piece of the LETC layer was laminated between pieces facing window darkened to very dark gray in the late after of glass shortly after the layer was extruded but without noon and evening. The experiment was conducted on a Sunny pre-drying the layer. The laminate was not scaled. The mea day in Michigan in August. The visible, white light transmis sured absorbances irreversibly increased with time at 80C in sion value.Y. of each laminate had previously been measured the center of the laminate, as shown by the data in Table 20. as a function of the temperature of that laminate. The tem 45 Also, the unsealed edges of the layer turned colorless and then perature of each laminate was measured and recorded yellow and showed no thermochromic activity. throughout the day. The temperature measurements were used to calculate the visible, white light transmission changes TABLE 20 throughout the day due to Sunlight exposure. 50 Absorbance The calculated transmission data are plotted as a function Hours Absorbance Absorbance Absorbance 565 the time of day for each of the thermochromic laminates in at 80 C. 425 nm 25 C. 425 nm.85 C. S65 mm 25 C. nm.85 C. FIG.50. The curves in FIG.50 show the remarkable sunlight O O.17 2.85 O.09 140 responsiveness of our LETC systems in our SRTTM configu 362 O.42 3.10 O16 2.06 rations. This kind of response allows the windows to darken 55 1130 O.82 8X O.29 2.52 and provide energy savings any time of the day, any day of the 2998 1.32 8X O42 2.60 year and at any location or orientation on a building or vehicle. This response is just due to the directness of the max as 3.5 absorbance units sunlight and the window tint just to the level desired to relieve heat load and glare, while still provide significant daylight 60 Example 289 ing. Similar Sunlight induced thermochromic tinting has been observed on numerous occasions for triple pane units and even double pane units glazed into a building. Occupants of A piece of the LETC layer was vacuum dried at room the building experienced relief from heat load and glare dur temperature for about 20 hours before lamination. The edge ing direct Sunlight exposure of the windows. 65 of the laminate was sealed with epoxy. This amount of drying In Examples 287 to 293, LETC layers were prepared by had little impact on stability as seen by the irreversible absor extrusion with the following composition: bance increases over time in the Table 21. US 7,525,717 B2

TABLE 21 TABLE 24

Absorbance Hours Absorbance Absorbance Absorbance 565 Absorbance at 80 C. 425 nm 25 C. 425 nm.85 C. S65 mm25 C. nm.85 C. Hours Absorbance Absorbance Absorbance 565 O O.18 1.60 O.O7 0.73 at 80 C. 425 nm 25 C. 425 nm.85 C. S65 mm 25 C. nm.85 C. 409 O.39 2.65 O.12 1.59 1035 O.81 2.66 0.27 1.92 2591 1.72 2.82 0.57 1.90 O O.17 1.99 O.11 O.94 10 2247 O.30 2.09 O.13 O.99 2967 O.33 2.10 O.14 1.02 Example 290 3687 O.35 1.81 O.14 O.86

A piece of the LETC layer was extruded where all of the 15 components were pre-dried prior to extrusion. The layer pro duced by extrusion was stored in vacuum over desiccant. This Example 293 pre and post dried layer was laminated between pieces of glass and the edges were sealed with epoxy. The measured A thermochromic layer like that in Example 292 was pre absorbance values given in Table 22 show much greater sta pared except the triethyleneglycol bis(2-ethylhexanoate) bility for thermochromic activity on exposure to 80 C. content of the layer was 20 weight %. The laminate again showed improved stability during storage at 80C as shown by TABLE 22 the absorbance values in Table 25. Absorbance Hours Absorbance Absorbance Absorbance 565 25 TABLE 25 at 80 C. 425 nm 25 C. 425 nm.85 C. S65 mm25 C. nm.85 C. Absorbance O O.23 1.82 O.10 O.87 Hours Absorbance Absorbance Absorbance 565 640 O.23 1.85 O.09 O.85 at 80 C. 425 nm 25 C. 425 nm.85 C. 565 nm 25 C. nm.85 C. 1701 O.33 1.71 O.09 O.77 2393 O.39 1.69 O.09 0.72 30 O O.22 240 O.14 1.18 2247 0.27 2.34 O.15 1.09 2967 0.27 2.15 O.15 1.07 3687 O.28 1.91 O.15 O.90 Example 291 35 The experiment in Example 290 was repeated in another Example 294 extrusion run the resulting laminate also showed improved stability as shown in the Table 23. Thermochromic layers with the following compositions: TABLE 23 40 Absorbance Absorbance Absorbance Absorbance Hours at 80 C. 42525 C. 42585 C. 56.525 C. 56585 C. Composition A Composition B O O.14 1.38 O.O7 O.67 0.1m (TBA).NiI 0.2m (TBA).NiBr 5O2 O16 1.36 O.O7 O.63 0.11m 4-(3-PhPr)Pyr 0.4m 1-butylimidazole 766 O.18 1.36 O.O7 O.64 45 O.3m TBAI O.2m TBABr 1847 O.19 1.45 O.O7 O.65 0.005m PhP O.SNPG O.07m. TMOLP in Butwar (RB-90 1 wt % Tinuwin (R) 405 in Butwar (RB-90 Example 292 50 A thermochromic layer was prepared by Solvent casting a were prepared by extrusion. A 0.03 cm thick layer with Com thermochromic layer from n-propanol. The layer contained: position A was placed on one side of a separator that was 0.07 m. NiI2(phP) 0.0076 cm thick layer of poly(ester terephthalate) which was O.7 m TBAI 55 excited on both sides by glow-discharge and labeled as South 0.2 mPhP wall “HB3775 Glow 2-sided available from Southwall Tech O.4 m. TMOLP nologies Inc. of Palo Alto, Calif. Two layers with Composi in ButVar(R) B-90 PVB tion B, totaling 0.09 cm thick, were placed on the other side of the separator. The polymer layer Stack was placed between the molal value were only with respect to the amount of PVB, 60 but the entire LETC layer was made 15 weight% in triethyl sheets of clear, plain, Soda-lime float glass and a laminate was eneglycol bis(2-ethylhexanoate). As part of the Solvent cast formed in a heated vacuum bag. The spectrum of the laminate ing process the layer was thoroughly dried at 80 C under was measured at 25 C, 45C, 65C and 85 C. By subtracting out nitrogen. The layer was laminated between pieces of glass a reference sample, the spectral data for the film stack alone and edge sealed with epoxy. The laminate showed improved 65 were calculated and plotted in FIG. 58. The values of L*, a, stability during storage at 80 C as shown by the absorbance b* and Y for films making up the laminate are given in the values in Table 24. Table 26 at various temperatures. US 7,525,717 B2 72 unheated 1 cm cuvette containing only the solvent was placed TABLE 26 in the reference beam of the spectrophotometer. The absorp tion spectrum was measured at various temperatures and the Temperature (C. wavelengths of maximum absorbance, W, and the absor 25 C. 45 C. 65 C. 85 C. bance at these values of W were recorded for each tempera ture of interest. Table 27 shows the LETC performance at Y 75.6 61.1 29.8 7.9 a: -12.7 -13.9 -11.8 -5.1 various temperatures for selected values of win a format b: 16.2 12.4 5.7 4.4 WAITIAT. A is the absorbance measured at a lower c:* 2O.S 18.3 13.1 6.7 temperature, T., and A is the absorbance measured at a 10 higher temperature, T., at the W indicated. For the examples in Table 27, the molarity values were calculated The information in Table 27 along with the key section of based on an assumed 5 ml total solution volume. Volume Table 27 give the formulations of liquid solution LETC sys changes due to components dissolved in the 5 ml of Solvent tems for Examples 295-1025. In each case the solution was were not considered. prepared by dissolving the materials indicated in 5 milliliters of the solvent listed at the heading of each section of Table27. 15 In Table 27 the Solvent May Act as Part or all of the LeL. In each example, Some of the Solution was placed in a 1 cm Each solution was cycled back and forth between hot and borosilicate cuvette, a small stir bar was placed in the cuvette cold and the amount of TC activity appeared remained con and the cuvette was placed in the sample beam of a Shimadzu sistent, i.e. on cooling the Solution decreased back to its UV-3101 PC spectrophotometer. The solution was stirred and original color and appearance. heated and the temperature was monitored with a thermo The key section also gives the synthesis for all the materials couple immersed in the Solution in the cuvette. A similar, used in LETC systems that are not commercially available.

TABLE 27 Exii M M LeL LeL HeL HeL Limax|A|ITIAh|Th Limax|AITIAhTh Limax|AITIAh|Th Solvent = 1,3-Butanediol 295 O.O2S Mi O.09 Hga 596 (0.156|25 | 1.843|85 6770.1721252.98885 Solvent = 3-Hydroxypropionitrile

296 O.O Mo 0.034 Hk 5910.1.52251.185 628O1325||1.03385 6800.17251.39685 Solvent = Diethylene glycol

297 O.O Mo O.2 Hfx 532O.37250.59585 57 OIO.362250.70485 298. O.O12 M O16 Hfz 6180.21251.05185 6750.224|25134485 7OOO.24425147385 299 O.O Mo O.11 Hfy 53510.297|25 |0.52685 57110.252|25 |0.581185 Solvent = e-Caprolactone 3OO O.O Mo O.92 Lbg 0.1 Hill 5370.309|250.63585 301 O.O Mh O.O3 Lu O.27 Hfz 66SO.OS4251.058S 7010.046251.5828S 7240.045251.74585 3O2 O.O Mo 2.6 Lbg 0.15 Hgh 5330.333|25 |0.933|85 5730.285|25 | 1.254|85 3O3 O.O Mo 1 Lbg 0.1 Hx 546O.19250.44685 585O127250.53985 632|0.08325|O.48685 3O4 O.O Mo O.19 Lbg 0.1 Hgi 5320.226|250.72285 5700.158|25 |0.981185 Solvent = Ethylene Glycol

3OS O.O Mo 2 Hfx S320.3392SO.6785 S700.3072SO.82685 306 O.O Mo 1 Hfx S3OO.2322SO4128S S700.1852SO4688S 307 O.O Mi O.O2 Hdy 5700.371|25 |0.969|85 6480.47|25 | 1.592.85 O.O22 Edga 3O8 O.O Mh O.O3 Hdy 5940.211250.763|85 6500.247|25 | 1.16985 O.O79 Z. 309 OO Mh O.O2 Hdy 630 (0.188|25 |0.966.85 665 (0.2425 |1314|85 7OOO.156.250.83785 0.37 w 31O O.O Mi O.O3 Hdy 570 (0.256|25 |0.6885 6480.245|25 |0.937.185 Solvent = Gamma Butyrolactone

311 O.O2 Mak 0.18 Lbw 0.2 Hfz. 7051.4672S3.4785 7561.4672S3.37285 312 O.O2 Mak 0.32 Lao 0.2 Hfz 6720.111252.09985 7040.133252.58385 7560.1071252.44485 313 O.O2 Mak 0.21 Lcg 0.2 Hfz 3521.06125585 7040.1752S2O1285 7560.154251958.85 314 O.O2 Mak 0.35 Le O.2 Hfz. 7050.7O6253.62185 7550.7031253.53985 315 O.O2 Mal O.78 Lbs 0.06 He 6170.04525|113685 6530.075.251.02685 7030.1251.06285 316 OO1 Mo 2.2 Lck 0.04 Hgz 565 (0.122|25 | 1.04685 6390.163|2512.03885 O.OS Hie 317 O.O1 Mo 2.24 Lck 0.1 He 596.O.O85250.843|85 633|O.O72|250.80485 6750.074250.9985 O.O2 Hie 318 O.O2 Mal O.28 Lck 0.003 Hbt 541|0.0852.50.49685 6650.118250.5918.5 757.0.051250.46785 O.2 Z. O.OO3 Hbb 319 O.O2 Mal O.12 Lck 0.31 Hbi 651|0.086|25 | 1.4985 702|0.086|25 | 1.342.85 7490.059251.0318.5 O.1 Hij 32O O.O2 Mal O.33 Lck 0.01 Hbu 521|O.O3925O.47485 63OO.25725173885 987|O.O73|250.26385 O.O2 Hdp O.2 Hfz

US 7,525,717 B2 107 108 Key added. A dark purple precipitate formed immediately. The The following materials were obtained from commercial precipitate was collected by vacuum filtration and washed sources or prepared as described below. with three 5 ml portions of water. The precipitate was dried at Ma=Bis(1-ethyl-1H-benzimidazole)diiodonickel(II) 50 C in a vacuum oven. To a flask were added 4.0 g nickel acetate tetrahydrate and Mat=Dibromobis 2-ethyl-2-(hydroxymethyl)propane-1,3- 216 ml n-butanol. The mixture was heated to 70 C under diolnickel(II) nitrogen and 7.9 g 57% hydroiodic acid were added. Follow To a flask were added 7.0 g of nickel acetate tetrahydrate, ing distillation of 60 ml to remove water and acetic acid, 5.4 130 ml of n-butanol, and 9.9 g of 48% hydrobromic acid. g of 1-ethylbenzimidazole were added and the reaction mix After distilling off 100 ml of solvent, 8.3 g of trimethylolpro ture was cooled to 15 C. The crystalline precipitate was fil 10 pane were added and the reaction mixture was cooled to 50 C. tered off, washed with 10 ml of 2-propanol and dried giving Following a slow addition of 90 ml of hexane, the mixture was 4.8g of dark green crystals. cooled to 5 C and the crystalline solid was filtered, washed with 10 ml of hexane, and dried giving 11.8g of light blue Mb-Diiodobis(tricyclohexylphosphine)nickel(II) crystals. To a flask were added 1.0 g nickel acetate tetrahydrate and 15 55 ml n-butanol. The mixture was heated to 70 C under Mbn=Tetrabutylammonium triiodo(triphenylphosphine) nitrogen and 2.0 g 57% hydroiodic acid was added. Following nickelate(II) distillation of 15 ml to remove water and acetic acid, a solu To a flask were added 4.2 g of nickel iodide hexahydrate tion of 2.6 g of tricyclohexylphosphine in 25 ml n-butanol and 25 ml of 2,2-dimethoxypropane. This mixture was stirred under nitrogen was added to the reaction mixture. Following under nitrogen at 22 C for 1.5 hours, when 50 ml of diethyl cooling to 5 C, the crystalline precipitate was filtered, washed ether were added. After stirring for several minutes, the liq with 5 ml of n-butanol and dried giving 2.0 g of reddish brown uids were decanted away from the solids, and the solids were crystals. rinsed twice with 25 ml of diethylether. To the solids were Me-Dibromobis(triphenylphosphine)nickel(II) added 12 ml n-butanol and after heating to 40 C, the mixture To a flask were added 3.0 g nickel bromide trihydrate and 25 was filtered. To the resulting solution, 3.7 g of tetrabutylam 75 ml n-butanol. The mixture was heated to 115 C under monium iodide were added along with 2.6 g of triphenylphos nitrogen and 5.8 g of triphenylphosphine were added. Fol phine, and the mixture was stirred at 40 C for 16 hours. After lowing distillation of 13 ml to remove water, the reaction cooling to 22 C, the product was filtered and washed with 20 mixture was cooled to 22 C. The crystalline solid was filtered, ml of tert-butyl methyl ether and dried, resulting in 3.5g of a washed with 5 ml of 2-propanol and dried giving 7.3 g of dark 30 brown solid. green crystals. Mbo–Tetrabutylammonium tetraiodonickelate(II) Mf-Diiodobis(triphenylphosphine)nickel(II) To a flask were added 50 g of nickel acetate tetrahydrate, 155 g tetrabutylammonium iodide, 650 ml of n-butanol, and To a flask were added 39.8g nickel acetate tetrahydrate and 136 g of 47% hydroiodic acid. The mixture was distilled 1800 ml n-butanol. The solution was heated to 70 C under 35 under a slow stream of nitrogen until 500 ml of solvent was nitrogen and 75.4 g 57% hydroiodic acid was added. Follow removed. After cooling the mixture to 50 C, 200 ml tert-butyl ing distillation of 625 ml to remove water and acetic acid, a methyl ether were added followed by seed crystals. Following solution of 92.3 g of triphenylphosphine in 910 ml n-butanol a slow addition of 600 ml of tert-butyl methyl ether, the at 70 C was added under nitrogen to the reaction mixture. mixture was cooled to 22 Cand the solid was filtered, washed Following cooling to 22 C, the crystalline solid was filtered, 40 with 100 ml of tert-butyl methyl ether, and dried giving 182g washed with 100 ml of 2-propanol, then 50 ml 2-propanol and of a red solid. dried giving 121.9 g of dark brown plates. MZZ-Cobalt(II) Nitrate Hexahydrate Mh=Cobalt(II) Bromide La=1,1-Bis(hydroxymethyl)cyclopropane Mi=Cobalt(II) Chloride Lb=1,2,4-Butanetriol Mo-Cobalt(II) Tetrafluoroborate hexahydrate 45 McCopper (II) Bromide Lc-1,2-Phenylenedimethanol Mr-Copper(II) Bromide Dihydrate Ld=1,2-Hexanediol Mt–Copper(II) Chloride Dihydrate Le=1,2-Propanediol Mv=Copper(II) Nitrate 2.5 Hydrate Lf Cis,cis-1,3,5-cyclohexanetriol dihydrate Mac-Dibromobis(1-ethyl-1H-benzimidazole)nickel(II) 50 Lh=1,3-Butanediol To a flask were added 709 g nickel bromide trihydrate and Li=1,3-Cyclohexanediol 16 L n-butanol. The mixture was heated to 90 C under nitro Lj=2.5-Bis(hydroxymethyl)-1,4-dioxane-2,5-diol gen and 760 g of 1-ethylbenzimidazole were added. Follow Lk=1,3-Propanediol ing distillation of 1.9L to remove water, the reaction mixture Lm=1,4-Dioxane was cooled to 40 C. The crystalline solid was filtered, washed 55 Lp=18-Crown-6 with IL of 2-propanol, then 500 ml of 2-propanol and dried Lq=1-Ethyl-1H-benzimidazole giving 1246 g of bright blue crystals. To a flask were added 100 g benzimidazole, 44 g sodium Maf Nickel(II) Bromide Hexahydrate hydroxide, 320 ml water and 480 ml tetrahydrofuran and the Maj=Nickel (II) Iodide Hexahydrate mixture was stirred under nitrogen. 157 g Diethyl sulfate Mak=Nickel(II) Nitrate Hexahydrate 60 were added slowly, maintaining a temperature of 40 C. After Mal–Nickel(II) Perchlorate Hexahydrate 2hrs at 40 C, the reaction was quenched with slow addition of Man=Nickel(II) Tetrafluoroborate Hexahydrate 100 ml concentrated hydrochloric acid. After washing with Mao-Bis(acetylacetonato)nickel(II) 150 ml hexane, the mixture was basified with 50 g sodium Mas-Nickel(II) bis(diisobutyldithiophosphinate) hydroxide and extracted with 275 ml ethyl acetate, then 225 0.55g Nickel(II) perchlorate hexahydrate was dissolved in 65 ml ethyl acetate. The solvent was removed, leaving an orange 0.5 ml of water. 0.60 g of a 50% sodium di(isobutyl)dithio oil, which was distilled under full vacuum to give 109.4g phosphinate water solution and another 2.5 ml water were clear colorless oil. US 7,525,717 B2 109 110 Lr 2,2,4-Trimethyl-1,3-Pentanediol Lck-Trimethylolpropane Ls=2,2-Dibutyl-1,3-Propanediol Lcl=Trimethylolpropane allyl ether Lt=2,2-Diethyl-1,3-Propanediol Lcm=Trimethylolpropane ethoxylate Lu=2,2'-Bipyridine Lcn-Trimethylolpropane propoxylate LV=2,3-Butanediol Lco-Triphenylphosphine Lw=2,3-Dimethyl-2,3-Butanediol Lcs=Water Ly=2.4-Pentanediol Lcz–Tetrahydrofurfuryl alcohol Lab=2-Bromo-2-Nitro-1,3-Propanediol Ldc=4-(3-Phenylpropyl)pyridine Lac-2-Butyl-2-Ethyl-1,3-Propanediol Ldd=6-Methyl-2,2'-bipyridine Lad=2-Ethyl-1,3-Hexanediol 10 Lae-2-Methyl-1,3-Propanediol Ldf=Bis(methylsulfinyl)methane Laf-2-Methyl-2,4-Pentanediol To a flask were added 4.05 g of methyl(methylthio)methyl Lag 2-Methyl-2-Propyl-1,3-Propanediol sulfoxide and 40 ml acetic acid. The mixture was cooled to 5 Lah=2-Methylenepropane-1,3-diol C under nitrogen and 3.7 ml of 30% hydrogen peroxide Lai=2-Phenyl-1,2-Propanediol 15 solution was added slowly. The mixture was allowed to warm Laj=2-Phenyl-1,3-Propanediol to 22 C and stirred under nitrogen for 16 hours. After removal Lal=Cyclohex-3-ene-1,1-diyldimethanol of most of the acetic acid, the product was purified by silica Lao-3-Methyl-1,3,5-Pentanetriol gel chromatography using 10% methanol in ethyl acetate to Lap=3-Phenoxy-12-Propanediol 20% methanol in ethyl acetate resulting in 3.0 g of a clear Laq3-Phenyl-1-propanol colorless oil as a mixture of stereo-isomers. Lar-4,4'-Dimethoxy-2,2'-bipyridine Ldg-Butyl sulfoxide Lav=2-Bis(2-hydroxyethyl)amino-2-(hydroxymethyl)pro Ldh–Tetrahydrothiophene 1-oxide pane-1,3-diol Ldo-2-Ethyl-2-(hydroxymethyl)butane-1,4-diol Lax-Diethylene glycol To a flask were added 1.5g diethyl ethylmalonate and 80 Laz Di(Trimethylolpropane) 25 ml of tetrahydrofuran and the solution was cooled to 5 C. 0.38 Lbc=3,3'-Oxydipropane-1,2-diol g Sodium hydride were added in Small portions and the reac Lbd-Dimethyl sulfoxide tion was stirred for 2 hours at 22 C. After cooling to 5 C, 1.6 Lbf–Ethanol g of ethyl bromoacetate were added drop wise and the reac Lbg. Ethylene Glycol tion mixture was allowed to stir at 22C under nitrogen for 16 Lbh=Glycerol 30 hours. After quenching with a few drops of water, the solvent Lbl=Lithium Salicylate was removed and the crude oil was dissolved in 20 ml tert Lbm=Lithium Trifluoroacetate butanol and 0.91 g sodium borohydride were added. The Lbo=Methanol mixture was heated to reflux under nitrogen and 1 ml metha Lbd-N,N-Dimethylformamide nol was added drop wise. After stirring for 30 minutes at Lbr=2,2-Dimethylpropan-1-ol 35 reflux, the mixture was cooled to 22 C and made acidic with Lbs=Neopenty1 Glycol slow addition of 3M hydrochloric acid. Following removal of Lbt-N-Propyl-N-pyridin-2-ylpyridin-2-amine Solvent, the product was purified by silica gel chromatogra To a flask were added 5.0 g 2,2'-dipyridiylamine, 4.9 g of phy using pure ethyl acetate resulting in a clear, colorless oil, pulverized potassium hydroxide and 45 ml of N,N-dimethyl 0.4g. formamide. After stirring for 1 hour under nitrogen, the mix 40 Ha=(S)-(-)-1-(2-Diphenylphosphino-1-naphthyl)isoquino ture was cooled to 5 Cand 5.0 g of 1-iodopropane were added. line The mixture was allowed to warm to 22 C and stirred for 5 Hb-2-(Dicyclohexylphosphino)ethyltrimethylammonium hours. After quenching with 45 ml water, the product was chloride extracted with ether and washed twice with water. Following Hc=1-(3-Phenylpropyl)-1H-benzimidazole removal of solvent, the product was purified by silica gel 45 To a flask were added 5 g benzimidazole and 75 ml tetrahy chromatography using 40% ethylacetate in hexane to give 4.8 drofuran under nitrogen and the solution was cooled to 10C g of nearly colorless oil. with stirring. 2.2 g Sodium hydride were added in small Lbu=Pentaethylene glycol portions and the reaction was stirred for 10 minutes. Lbv=Pentaerythritol 1-Bromo-3-phenylpropane was added and the reaction mix Lbw=Pentaerythritol ethoxylate 50 ture was heated to 40 C for 5 hrs. After cooling to 5 C, the Lcc=Tetrahydropyran-2-methanol reaction was quenched with slow addition of 100 ml water. Lcd-Tributylphosphine oxide After the tetrahydrofuran was removed of by rotovap, the Lcg 2-(Hydroxymethyl)-2-propylpropane-1,3-diol mixture was extracted with 100 ml ethyl acetate and washed A solution 15 ml water and 6 g sodium hydroxide was with 25 ml water and the solvent was removed on the rotovap. prepared in a flaskand cooled to 0-5C under nitrogen. Form 55 The product was purified by column chromatography using aldehyde, (37%), 34.4g, was added drop-wise with vigorous 40% ethyl acetate in hexane resulting in a light yellow oil stirring, while keeping temperature below 10 C. Valeralde which crystallized in the freezer. hyde, 10.3 g, was added in Small portions. The reaction was Hg 2,2'-Butane-1,1-diylbis(1-propyl-1H-benzimidazole) heated to 60 C for five hours, then saturated with sodium chloride and extracted with 3x50 ml ether. The ether layer 60 2,2'-Methylenebis(1H-benzimidazole) was dried over sodium sulfate, filtered and the solvent was removed. Methanol, 10 ml, was added and the solution was To a flask were added 20 g polyphosphoric acid. After cooled in the freezer for 16 hours. The product was filtered heating to 90 C under nitrogen, a mixture of 5.0 g 1.2-phe off, washed with a little methanol and dried in a vacuum oven. nylenediamine and 2.4 g malonic acid were added. The reac Lch=2-(Hydroxymethyl)-2-methylpropane-1,3-diol 65 tion mixture was heated to 180 C for 4 hours, then cooled to Lci=2-(Hydroxymethyl)propane-1,3-diol 150 C and poured into 40 ml water. The mixture was basified Lci=2-(Hydroxymethyl)-2-nitropropane-1,3-diol with aqueous ammonium hydroxide. After cooling to 5 C, the US 7,525,717 B2 111 112 product was filtered off and washed with water. The solid was for 72 hrs. The solid was filtered and washed with a small reslurried in 200 ml hot acetonitrile, cooled, filtered and dried amount of ethanol. The product was recrystallized from 90% leaving 2.7 g of a gray Solid. ethanol and dried, resulting in 2.8g of an off-white solid. Hr-1,2-Dimethylimidazole 2,2'-butane-1,1-diylbis(1-propyl-1H-benzimidazole) Hs=1,3-Bis(diphenylphosphino)propane To a flask were added 0.79g 2,2'-methylenebis(1H-benz Hv=14.8, 11-Tetrathiacyclotetradecane imidazole) and 20 ml N,N-dimethylformamide under nitro Hx=1,8-Naphthyridine gen. 0.42 g sodium hydride were added in portions and the Hy=10-Methyl-10H-phenothiazine mixture was stirred 20 minutes. 1.74 g 1-iodopropane were 10 Hab=1-Benzyl-2-methyl-1H-benzimidazole added slowly and the mixture was stirred at 22 C for 16 hrs. To a flask were added 2.5g, 2-methylbenzimidazole, 3.9 g, After quenching with the slow addition of 40 ml water, the potassium carbonate, 60 ml N,N-dimethylformamide and the product was extracted with ethyl acetate and washed with mixture was stirred under nitrogen. 3.6 g Benzyl chloride water. Solvent removal resulted in an oil which was purified were added and the mixture was heated to 60 C for 16 hours. by silica gel chromatography using 25% ethyl acetate in 15 The reaction was quenched with 80 ml water and cooled to 22 hexane to give 0.9 g of a light yellow oil which crystallized on C. The product was extracted twice with 50 ml ethyl acetate Standing. and washed with water. Following removal of solvent, the Hh=1,1'-Bis(diphenylphosphino)ferrocene product was dissolved in 100 ml hexane and washed with two Hk=1,1'-Diethyl-1H, 1'H-2,2'-bibenzimidazole portions of water. After drying the hexane layer over Sodium To a flask were added 2.0 g 1-ethyl-1H-benzimidazole and sulfate, the mixture was filtered and stripped down to an 25 ml tetrahydrofuran under nitrogen. To this solution was orange oil. added 20 ml n-butyllitium (1.6M) and the mixture was heated to 60 C for 72 hours. After cooling to 22 C, the reaction was Hac=1-Benzyl-2-phenyl-1H-benzimidazole quenched with water and extracted with ethyl acetate. Fol To a flask were added 3 g 2-phenylbenzimidazole, 2.8 g. lowing solvent removal, the product was dissolved in 8.5 ml 25 potassium carbonate, 40 ml N,N-dimethylformamide and the hot ethyl acetate and 20 ml of hexane were added. After mixture was stirred under nitrogen. 3.6 g Benzyl chloride cooling to 5 C, the product precipitated and was filtered, were added and the mixture was heated to 75 C for 8 hrs. The washed with hexane, and dried giving 0.42 g pale yellow reaction was cooled to 50C and quenched with 40 ml of water solid. and cooled to 5 C. The product was filtered, washed with Hl=1,2-Benzisoxazole 30 water. The product was recrystallized by dissolving in 57 ml Hm=2,2'-(1,2-Phenylene)bis(1-ethyl-1H-benzimidazole) acetonitrile at reflux and 39 ml water were added. After cool ing to 5C, the product was filtered, washed and dried giving 2,2'-(1,2-Phenylene)bis(1H-benzimidazole) 3.1 g. Had=1-Benzyl-2-pyridin-2-yl-1H-benzimidazole To a flask were added 50 g polyphosphoric acid. After 35 To a flask were added 2.0 g 2-(2-pyridyl)benzimidazole, heating to 90 C under nitrogen, a mixture of 2.7 g 1.2-phe 1.8 g. potassium carbonate, 30 ml N,N-dimethylformamide nylenediamine and 2.1 g phthalic acid were added. The reac and the mixture was stirred under nitrogen at 10 C. 1.5 g. tion mixture was heated to 180 C for 4 hours, then cooled to benzyl chloride were added and the mixture allowed to warm 130C and poured into 150 ml water. The mixture was basified to 22 C and stirred for 3 hours. Another 0.3 g benzyl chloride with aqueous ammonium hydroxide. After cooling to 5 C, the 40 was added and the reaction was stirred at 22 C for another 16 product was filtered and washed with water. After drying, 3.3 hours. The reaction was quenched with 40 ml water and the g of a gray Solid remained. product was filtered and washed with water. The product was dissolved in 10 ml ethanol and 15 ml of water were added. 2,2'-(1,2-Phenylene)bis(1-ethyl-1H-benzimidazole) After cooling to 5 C, the product was filtered, washed and 45 dried resulting in 2.4 g of off-white solid. To a flask were added 1.5 g 2,2'-(1.2-phenylene)bis(1H Hae=1-Benzyl-2-(benzylsulfanyl)-6-methyl-1H-benzimida benzimidazole) and 30 ml N,N-dimethylformamide and the Zole mixture was cooled to 5 C under nitrogen. 0.48 g Sodium To a flask were added 2.0 g 2-mercapto-5-methylbenzimi hydride were added in portions and the reaction mixture was dazole, 4.2 g potassium carbonate, 30 ml N,N-dimethylfor stirred for 20 minutes. 1.9 g Iodoethane were added and the 50 mixture was allowed to warm to 22 C and was stirred for 1 mamide and 3.9 g benzyl chloride. The reaction mixture was hour. The mixture was quenched slowly with 50 ml water and heated to 60C for 16 hours, then cooled to 50C and quenched cooled to 5 C. The product was filtered and washed with with 60 ml water and cooled to 5 C. The solid was filtered and water. The product was dissolved in 13 ml hot acetonitrile, washed with water and then recrystallized by dissolving in 50 cooled, filtered and washed with acetonitrile and dried result 55 ml hot acetonitrile and adding 10 ml of water. After cooling to ing in 1.2 g of an off-white solid. 5C, the product was filtered, washed and dried resulting in 3.5 Hn=2,2'-ethene-1,2-diyldipyridine g white solid as a mixture of the 5-methyl and 6-methyl Ho-2,2'-(1,2-phenylene)bis(1,3-benzothiazole) isomers. To a flask were added 50 g polyphosphoric acid. After Hag1-Benzyl-4-methyl-1H-benzimidazole heating to 90 C under nitrogen, a mixture of 3.13 g 2-ami 60 nophenol and 2.1 g phthalic acid were added. The reaction 4-methyl-1H-benzimidazole mixture was heated to 140C for 4 hours, then cooled to 90 C and poured into 150 ml water. The mixture was basified by To a flask were added 2.0 g 2,3-diaminotoluene, 1.0 g 90% adding Sodium carbonate in Small portions and the product formic acid and 30 ml 5M hydrochloric acid and the mixture was extracted with ethyl acetate and washed with water. Fol 65 was heated to 90 C under nitrogen for 4 hours. After cooling lowing removal of Solvent, the product was dissolved in a to 22 C, the mixture was basified with aqueous ammonium minimum amount of hot ethanol and allowed to stand at 22C hydroxide and the product was removed by filtration and US 7,525,717 B2 113 114 washed with water. The product was purified by column solid crystallized. The solid was recrystallized from 30 ml chromatography using pure ethyl acetate resulting in 1.0 g (2:1, V/v) ethanol/water. The solid was dried under vacuum brown solid. for 3 hrs at 50 C. 3.7 g of a white solid was obtained. Ham=2-(1H-Benzimidazol-1-yl)ethanol 1-Benzyl-4-methyl-1H-benzimidazole To a flask were added 2.3 g benzimidazole and 40 ml tetrahydrofuran and the mixture was cooled to 10 C under To a flask were added 1.0 g 4-methyl-1H-benzimidazole, nitrogen. 1.0 g Sodium hydride were added in portions and 1.6 g potassium carbonate, 25 ml N,N-dimethylformamide the reaction mixture was stirred for 20 minutes. 4.0 g 2-To and the mixture was stirred under nitrogen. 1.4 g Benzyl doethanol were added and the mixture was heated to 50 C for chloride were added and the mixture was heated to 60C for 16 10 16 hours. The mixture was quenched slowly with 50 ml water, hours. Another 0.4 g of benzyl chloride were added and the extracted twice with ethyl acetate and dried over sodium reaction was heated to 70 C for 24 hours. The reaction was sulfate. Following filtration and solvent removal, the product cooled to 50 C and quenched with 50 ml water and extracted was purified by Silica gel chromatography using 25% metha with ethyl acetate. After washing with water, the solvent was nol in ethyl acetate. A solid was obtained that was dissolved in removed and the product was purified by column chromatog 15 a hot mixture of 10% methanol in ethyl acetate, cooled, fil raphy using a gradient from 40% ethyl acetate in hexane to tered and dried giving 1.4 g white solid. 75% ethyl acetate in hexane. Following removal of the sol Han-2-2-(Diphenylphosphino)phenyl-1-methyl-1H-benz vent, the partially crystallized product was dissolved in 20 ml imidazole acetonitrile and treated with 0.1 g activated carbon. After refluxing for 20 minutes, the mixture was filtered through 2-(2-Bromophenyl)-1H-benzimidazole celite and the solvent was removed leaving a yellow oil which crystallized on standing, 1.0 g. To a flask were added 80 g methanesulfonic acid and 8 g Hah=1-Benzyl-1H-benzimidazole phosphorus pentoxide and the mixture was heated to 60 C To a flask were added 2 g benzimidazole, 3.5g potassium under nitrogen until the solids had completely dissolved. To carbonate, 20 ml N,N-dimethylformamide and the mixture 25 this solution was added 2.7 g 1.2-phenylene diamine and 5.0 was stirred under nitrogen. 3.2 g Benzyl chloride were added g 2-bromobenzoic acid and the mixture was heated to 100 C and the mixture was heated to 50 C for 16 hrs. The reaction for 30 minutes. The mixture was poured onto 300 ml ice water was quenched with 40 ml water and 7 ml 3M hydrochloric and basified with the addition of small portions of sodium acid and cooled to 5 C. The product was filtered and washed carbonate. Following filtration of the solid and washing with with water. The product was recrystallized by dissolving in 10 30 water, the crude product was dissolved in 85 ml hot ethanol, ml 2 propanol at reflux, hot filtered and 30 ml hexane were filtered and 9 ml of water was added. After cooling to 5C, the added. After cooling to 5 C, the product was filtered, washed product was filtered and washed with 50% ethanol and dried, with hexane and dried giving 1.6 g. giving 3.85g off-white solid. Hai=1-Ethyl-1H-imidazo[4,5-b]pyridine 2-(2-Bromophenyl)-1-methyl-1H-benzimidazole To a flask were added 0.5g 4-azabenzimidazole and 10 ml 35 N,N-dimethylformamide and the mixture was cooled to 10C To a flask were added 3.3 g 2-(2-bromophenyl)-1H-benz under nitrogen. 0.18 g Sodium hydride were added in por imidazole and 100 ml tetrahydrofuran and the mixture was tions and the reaction mixture was stirred for 20 minutes. 0.71 cooled to 10 C under nitrogen. 0.63 g Sodium hydride were g Diethylsulfate were added and the mixture was allowed to added in portions and the reaction mixture was stirred for 20 warm to 22 C and was stirred for 16 hours. The mixture was 40 minutes. 2.0 g Dimethylsulfate were added and the mixture quenched slowly with 30 ml 1M hydrochloric acid and the was heated to 22C for 30 minutes. The mixture was quenched aqueous layer was washed with ethyl acetate. After basifica slowly with 100 ml water, extracted with ethyl acetate and tion with sodium hydroxide, the product was extracted twice then extracted into a 1M hydrochloric acid solution. The with ethyl acetate and dried over sodium sulfate. Following solution was washed with ethyl acetate and then basified with filtration and solvent removal, the product was purified by 45 3M sodium hydroxide. Following extraction with ethyl silica gel chromatography using 5% methanol in ethyl acetate acetate and solvent removal, the solid was dissolved in a hot to 12% methanol in ethyl acetate. 0.4 g Ofan oil was obtained. mixture of 20 ml hexane with 4 ml 2-propanol. After cooling Haj=1-Ethyl-1H-benzimidazole to 5 C, the product was filtered, washed with hexane and dried To a flask were added 100 g benzimidazole, 44 g Sodium giving 2.9 g of a white solid. hydroxide, 320 ml water and 480 ml tetrahydrofuran and the 50 mixture was stirred under nitrogen. 157 g Diethyl sulfate 2-2-(Diphenylphosphino)phenyl-1-methyl-1H were added slowly, maintaining a temperature of 40 C. After benzimidazole 2hrs at 40C, the reaction was quenched with slow addition of 100 ml concentrated hydrochloric acid. After washing with To an oven dried flask that was purged with nitrogen was 150 ml hexane, the mixture was basified with 50 g Sodium 55 added 1.5g 2-(2-bromophenyl)-1-methyl-1H-benzimidazole hydroxide and extracted with 275 ml ethyl acetate, then 225 and 50 ml dry tetrahydrofuran. The solution was cooled to ml ethyl acetate. The solvent was removed, leaving an orange -70 C and 3.9 ml of a 1.6M solution of n-butyllithium in oil, which was distilled under full vacuum to give 109.4g hexanes was added drop wise. After stirring 1 hour at less than clear colorless oil. -60 C, 1.4 g chlorodiphenylphosphine was added drop wise and the mixture was allowed to warm to 22 C. The mixture Hak=1-Ethyl-2-(1,3-thiazol-4-yl)-1H-benzimidazole 60 was quenched with 100 ml of nitrogen-purged water and 5.0 g Thiabendazole and 1.31 g sodium hydroxide were extracted with nitrogen-purged ethyl acetate. Following Sol added to 40 ml of tetrahydrofuran. The white slurry was vent removal, the solid was dissolved in 10 ml of hot, nitro stirred under nitrogen and 4.6 g of diethylsulfate was added gen-purged ethanol and 7 ml of nitrogen-purged water was dropwise. The mixture was stirred at 50 C for 16 hours. The added. After cooling to 5 C, the product was filtered and mixture was quenched with 75 ml of water and then extracted 65 washed with 50% ethanol that was nitrogen-purged and dried with 75 ml or ethyl acetate. The organic layer was washed giving 1.3 g off-white solid. with 15 ml of water. Following solvent removal, an off-white Hao-1-Methyl-1H, 1'H-2,2'-bibenzimidazole US 7,525,717 B2 115 116 1H, 1'H-2,2'-Bibenzimidazole 40 ml water, extracted with ethyl acetate and washed with water. Following solvent removal, the product was purified by To a flask were added 10.8 g. 1.2-phenylene diamine, 2.65 silica gel chromatography using straight 67% ethyl acetate, g hexachloroacetone and 50 ml ethylene glycol. The mixture 24% hexane and 9% methanol. An oil was obtained. was mixed and heat to 55C under nitrogen and sonicated for Hay=1-Propyl-1H-benzimidazole 3 hours. After cooling to 22 C, the solid was filtered and To a flask were added 2.0 g benzimidazole, 3.5g potassium washed with acetone and dried leaving 1.3 g yellow solid. carbonate, 4.3 g 1-iodopropane and 20 ml N,N-dimethylfor mamide. The mixture was heated to 45 C under nitrogen for 1-Methyl-1H, 1'H-2,2'-bibenzimidazole 16 hours and then quenched with 30 ml water and the product 10 was extracted with ethyl acetate. Following removal of the To a flask were added 1.2 g 1H, 1'H-2,2'-bibenzimidazole, Solvent, the product was purified by silica gel chromatogra 0.45 g sodium hydroxide, 100 ml N,N-dimethylformamide phy using 66% ethyl acetate in hexane. The brown oil was and 1.4 g dimethylsulfate. The mixture was heated to 45 C again purified by silica gel chromatography using ethyl under nitrogen for 16 hours and another 0.45 g sodium acetate, giving a slightly yellow oil 1.5 g. hydroxide and 2.8 g. dimethylsulfate were added and the 15 Haz-N,N-Dimethyl-2-pyridin-2-ylethanamine mixture was stirred at 45 C for 24 hours. Another 4.2 g of Hbb=N-Methyl-2-pyridin-2-ylethanamine dimethylsulfate were added and the mixture was stirred at 45 Hbc=2-Pyridin-2-yl-1H-benzimidazole C for 24 hours, then cooled to 22 C and quenched with 350 ml Hbf N,N-Dimethyl-1-pyridin-2-ylmethanamine water. The off-white solid was filtered and washed with water. Hbj=2,1,3-Benzothiadiazole After dissolving the product in 125 ml hot ethanol, 44 ml Hbl=2,2'-Propane-2,2-diylbis(1-propyl-1H-benzimidazole) water were added and the solution was cooled to 5C, filtered, washed with 50% ethanol and dried leaving 0.5g white solid. 2,2'-Propane-2,2-diylbis(1H-benzimidazole) Haq-1-Methyl-2-pyridone Har–1-Methyl-1H-benzimidazole To a thick walled glass tube was added a mixture of 5.8 g. Has=1-Methyl-1H-imidazole 25 1.2-phenylene diamine dihydrochloride and 1.5 g malononi Hat=1-Phenyl-1H-benzimidazole trile. The tube was flame-sealed underfull vacuum and heated to ~220 C for 1.5 hours causing the mixture to turn black. N-Phenylbenzene-1,2-diamine After cooling to 22 C, the black material was added to 60 ml 1M hydrochloric acid and stirred and heated to 50 C for To a pressure reaction bottle was added 10 g 2-nitrodiphe 30 several hours. After adding 150 mg activated carbon, the nylamine, 0.5 g 5% palladium on carbon and 100 ml 95% mixture was brought to reflux and filtered through celite. The ethanol. The mixture was hydrogenated at 22 C and 40 psi clear filtrates were basified with aqueous ammonium hydrox hydrogen for 2 hours. Following filtration through celite and ide resulting in a cream colored solid which was filtered and solvent removal, an oil was obtained that crystallized on washed with water. After re-slurrying the solid in hot water Standing. 35 and filtering, the product was dried resulting in 2.5 g. 1-Phenyl-1H-benzimidazole 2,2'-Propane-2,2-diylbis(1-propyl-1H-benzimida zole) To a flask were added crude N-phenylbenzene-1,2-di amine, 9.7 g formamidine acetate and 175 ml 2-methoxyetha 40 To a flask were added 1.4 g 2,2'-propane-2,2-diylbis(1H nol and the mixture was heated to reflux under nitrogen for 30 benzimidazole) and 30 ml tetrahydrofuran and the mixture minutes. After cooling to 22 C, the solvent was removed and was cooled to 10 C under nitrogen. 0.61 g Sodium hydride the mixture was dissolved in ethyl acetate and washed with were added in portions and the reaction mixture was stirred water. Following removal of the solvent, the product was for 20 minutes. 2.6 g 1-iodopropane were added and the purified by silica gel chromatography using 50% ethylacetate 45 mixture was stirred at 22 C for 3.5 hours. The mixture was in hexane giving a tan oil. quenched slowly with 30 ml water and stirred 16 hours. After Hau=1-Phenyl-1H-imidazole cooling to 5 C, the solid was filtered and washed with water Hav=2-Methyl-1-propyl-1H-benzimidazole and purified by silica gel chromatography using 25% ethyl To a flask were added 2.0 g 2-methylbenzimidazole and 40 acetate in hexane to 50% ethyl acetate in hexane. 1.4 g of ml tetrahydrofuran and the mixture was cooled to 10 C under 50 off-white solid was obtained. nitrogen. 0.9 g Sodium hydride were added in portions and Hbn=2,2'-Propane-2,2-diylbis(1,3-benzothiazole) the reaction mixture was stirred for 20 minutes. 3.9 g 1-io To a flask were added 50 g polyphosphoric acid. After dopropane were added and the mixture was heated to 45 C for heating to 70 C under nitrogen, a mixture of 3.13 g 2-ami 6 hours. The mixture was quenched slowly with 40 ml water, nothiophenol and 1.65 g dimethylmalonic acid was added. extracted twice with ethyl acetate and washed with water. 55 The reaction mixture was heated to 150 C for 2 hours, then Following solvent removal, the product was purified by silica 165 C for 3 hours. After cooling to 80 C, the mixture was gel chromatography using pure ethyl acetate to 5% methanol poured into 100 ml water. The slurry was cooled to 5 C. in ethyl acetate. A pale yellow oil was obtained. filtered and the solid was washed with water. The solid was Haw=2-Phenyl-1-propyl-1H-benzimidazole added to a mixture of 20 ml ethanol and 210 ml water at 50C To a flask were added 3.0 g 2-phenylbenzimidazole and 60 60 and basified with aqueous ammonium hydroxide. After cool ml tetrahydrofuran and the mixture was cooled to 10 C under ing to 10 C, the solid was filtered and washed with water. The nitrogen. 0.41 g Sodium hydride were added in portions and solid was dissolved in 50 ml hot ethanol, hot filtered and 5 ml the reaction mixture was stirred for 20 minutes, then cooled to water was added and the solution was cooled to 5 C. Follow 10 C. 3.1 g 1-iodopropane were added and the mixture was ing filtration, the white solid was washed with 75% ethanol heated to 55 C for 16 hours. Another 0.8 g. 1-iodopropane 65 and dried. were added and the temperature was held at 55 C for two Hbs=N-Pyridin-2-ylpyridin-2-amine hours. The mixture was cooled to 22 C, quenched slowly with Hbt-2,2'-Ethane-1,2-diyldipyridine US 7,525,717 B2 117 118 To a Pressure reaction bottle was added 6.9 g of 2,2'-bis Hdm=4-(3-Phenylpropyl)pyridine (dipyridyl)ethene, 0.6 g 5% palladium on carbon, and 200 ml Hdo-4-Pyridinecarboxaldehyde ethanol. The mixture was purged with hydrogen and then Hdp=4-Tert-butylpyridine hydrogenated under 40 psi hydrogen for 16 hours. The cata Hds=5-Hydroxy-2-methylpyridine lyst was filtered off on a bed of celite. The solvent was removed and the residue was dissolved in 40 ml of hot hexane, Hdt=5-Methoxy-1-methyl-1H-benzimidazole and filtered hot. After the addition of seed crystals and cooling To a flask were added 2.5 g 5-methoxybenzimidazole and to 10 C, the product was filtered, washed with hexane and 40 ml tetrahydrofuran and the mixture was cooled to 10 C dried, resulting in 5.3 g of an off-white solid. under nitrogen. 0.9 g Sodium hydride were added in portions Hbu=2,2'-Methylenedipyridine 10 and the reaction mixture was stirred for 20 minutes. 2.6 g. To a flask were added 5 g of 2,2'-dipyridylketone, 3.2 g of Dimethylsulfate were added and the mixture was allowed to potassium hydroxide, 100 ml of diethyene glycol and 3.4 g of warm to 22 C and was stirred for 2 hours. The mixture was hydrazine hydrate. The mixture was heated to 10° C. under quenched slowly with 50 ml water and the tetrahydrofuran nitrogen for 1 hour, then heated to 150 C for 2 hours, and then was removed by distillation. The product was extracted twice 180C for 3 hours. Aftercooling to 22 C, 150 ml of water were 15 with ethyl acetate and washed with water. Following solvent added and the mixture was extracted with 150 ml ethyl removal, the product was purified by silica gel chromatogra acetate. Afterwashing the ethylacetate layer twice with 50 ml phy using 5% methanol in ethyl acetate to 10% methanol in of water, the solvent was removed and the product was puri ethyl acetate. 2.2 g Of off-white solid was obtained. 1.6 g. Of fied by silica gel chromatography using 95% ethyl acetate this product was dissolved in 7 ml hot toluene and 25 ml with 5% methanol to give 1.9 g of a light yellow oil. hexane were added along with a seed crystal. After cooling to Hbv=2,2'-Propane-1,3-diyldipyridine 5 C, the crystalline solid was filtered, washed with hexane and To a flask were added 93 g of 2-picoline, 21 g of 2-vinylpy dried to give 1.2 g of a white solid as a mixture of the 5-meth ridine, 1 g of Sodium and a trace of hydroquinone. The mix oxy and 6-methoxy isomers. ture was heated to 130 C under nitrogen for 2 hours. After Hdv=8-Methyl-3,4-dihydro-2H-1.3thiazino.3.2-abenz cooling to 22 C, 200 ml of water were added and the mixture 25 imidazole was extracted with 150 ml diethyl ether. After washing the To a flask were added 2 g 2-mercapto-5-methylbenzimida diethyl ether layer twice with 100 ml of water, and twice with Zole, 4.2 g potassium carbonate, 4.0 g 1,3-diiodopropane and 50 ml of 10% sodium sulfite, the solvent was removed and the 60 ml N,N-dimethylformamide. The mixture was heated to product was purified by vacuum distillation to give 7.5g of a 50 C under nitrogen for 5 hours and then cooled to 22 C. The light yellow oil. 30 reaction was quenched with 100 ml water and the product was HbZ-2,4,6-Trimethylpyridine extracted twice with ethyl acetate and washed twice with Hca-2,4-Pentanedione water. Following removal of the solvent, the product was Hcb=2,5-Lutidine recrystallized by dissolving in a hot mixture of 50 ml hexane Hcg=1H-Benzimidazol-2-ylmethanol with 10 ml 2-propanol. After cooling to 5 C, the product was Hci=2'-(Diphenylphosphino)-N,N-dimethylbiphenyl-2- 35 filtered, washed with hexane and dried giving 0.63 g of an amine off-white solid. Hc=2-(Diphenylphosphino)-6-methylpyridine Hdx=6,6'-Dibromo-2,2'-bipyridine Hcn=2-Mercapto-1-methylimidazole Hdy=6,6'-Dimethyl-2,2'-bipyridine Hco-2-Mercapto-5-methylbenzimidazole HdZ-6-Butyl-6-methyl-2,2'-bipyridine Hcp=Pyridine-2-thiol 40 Hcq=Pyrimidine-2-thiol Hcr-2-Methyl-1H-benzimidazole 2-(Benzyloxy)-6-chloropyridine Hcs=2-Methylbenzothiazole Hct=1H-Benzimidazol-2-ol To a flask were added 5.0 g 6-chloro-2-hydroxypyridine, Hcv-Pyridin-2-ylmethanol 45 5.3 g potassium carbonate and 75 ml N,N-dimethylforma Hcw=3-(Diethylamino)-1,2-propanediol mide. After cooling to 5 C under nitrogen, 5.9 g of benzyl Hcx=3,3-Dimethyl-2,4-pentanedione chloride were added drop wise and the reaction mixture was Hcz-3,6-Dithia-1,8-octanediol warmed to 60C for 3 hours. After cooling to 10 C, the reaction Hdc=3-Methyl-2,2'-bipyridine mixture was quenched with 75 ml of water and the product To a flask were added 1.0 g 2-bromo-3-methylpyridine and 50 was extracted with ethyl acetate and washed with water. Fol 10 ml of dry tetrahydrofuran. The solution was purged with lowing solvent removal, the product was purified by silica gel nitrogen and 34 mg tetrakis(triphenylphosphine)palladium chromatography using 5% ethyl acetate in hexane to give a was added followed by 17.4 ml of a 0.5M solution of 2-py clear colorless oil 7.9 g. ridylzinc bromide intetrahydrofuran. The mixture was stirred at 22 C for 24 hours, then 40C for 72 hours. The mixture was 55 2-(Benzyloxy)-6-butylpyridine poured into a solution of 5 g EDTA, 2 g sodium carbonate and 40 ml water. The product was extracted twice with diethyl To a flask were added 2.0 g 2-(benzyloxy)-6-chloropyri ether, washed with water and dried over sodium sulfate. Fol dine, 5.0 ml 1-methyl-2-pyrrolidinone and 50 ml of dry tet lowing filtration and solvent removal, the product was puri rahydrofuran. After cooling to 5 C under nitrogen, 0.16 g fied by silica gel chromatography using 48% ethyl acetate, 60 iron(III) acetylacetonate were added followed by drop wise 48% hexane and 4% methanol. A slightly yellow oil remained addition of 8.5 ml of a 2M solution of butylmagnesium bro 0.38 g. mide in tetrahydrofuran. After stirring for 1 hour at 22 C, the Hde=4,4'-Dimethoxy-2,2'-bipyridine reaction was cooled to 10C and quenched with 20 ml aqueous Hdf 3,4-Dimethoxyaniline ammonium chloride. The mixture was diluted with water and Hdh=Phenyl(pyridin-4-yl)methanone 65 extracted with hexane. After washing with water and removal Hdi-N,N-Dimethylpyridin-4-amine of solvent, the product was purified by silica gel chromatog Hd=4-Hydroxypyridine raphy using 10% ethylacetate in hexane to give 1.6 g of an oil. US 7,525,717 B2 119 120 6-Butylpyridin-2-ol To a flask were added 1.0 g of di(tert-butyl)chlorophos phine and 5 ml of dichloromethane under nitrogen. After slow To a pressure reaction bottle were added 1.6 g 2-(benzy addition of 0.25g of water, the mixture was stirred at 22 C for loxy)-6-butylpyridine, 0.2 g 5% palladium on carbon and 50 30 minutes and the solvent was removed leaving a solid. After ml ethanol. The mixture was hydrogenated at 22 C and 40 psi purification by sublimation, 0.9 g of a white solid was hydrogen for 16 hours. Following filtration through celite and obtained. solvent removal, an oil was obtained that crystallized on Hfi=Ditetrabutylammonium malonate standing to give 0.9 g. To a flask were added 3.1 g malonic acid, 24.6 g of a 55-60% solution of tetrabutylammonium hydroxide in water, 6-Butylpyridin-2-yl trifluoromethanesulfonate 10 13 ml water and 75 ml 2-propanol. After heating to 50C under nitrogen for 1 hour, the solvent was removed and another 30 To a flask were added 0.9 g 6-butylpyridin-2-ol and 10 ml ml of 2-propanol were added and removed by distillation pyridine and the mixture was cooled to 10 C under nitrogen. under reduced pressure. After drying, an oil was obtained. 1.85g trifluoromethanesulfonic anhydride were added slowly Hf=Ditetrabutylammonium phenylphosphonate and the reaction mixture was allowed to warm to 22 C and 15 To a flask were added 2.0 g phenylphosphonic acid, 111.0 stirred for 16 hours. g of a 55-60% solution of tetrabutylammonium hydroxide in After cooling to 5 C, the mixture was quenched with 20 ml water and 30 ml 2-propanol. After heating to 50 C under of water and extracted twice with hexane. After drying over nitrogen for 1 hour, the solvent was removed and another 30 sodium sulfate, the solution was filtered and the solvent was ml of 2-propanol were added and removed by distillation removed. Purification by Silica gel chromatography using 5% under reduced pressure. After drying, a pinkish oil was ethyl acetate in hexane resulted in 1.2g of a clear colorless oil. obtained. Hfl-Ditetrabutylammonium succinate 6-Butyl-6-methyl-2,2'-bipyridine To a flask were added 3.5 g. Succinic acid, 26.4 g of a 55-60% solution of tetrabutylammonium hydroxide in water, To a flask were added 1.2 g 6-butylpyridin-2-yl trifluo 25 13 ml water and 75 ml 2-propanol. After heating to 50C under romethanesulfonate, 0.36 g lithium chloride and 10 ml dry nitrogen for 1 hour, the solvent was removed and another 75 tetrahydrofuran. Addition of 12 ml of a 0.5M solution of ml of 2-propanol were added and removed by distillation 6-methyl-2-pyridylzinc bromide in tetrahydrofuran was fol under reduced pressure. After drying, an oil was obtained. lowed by addition of 242 mg of tetrakis(triphenylphosphine) Hfo=Ethyldiphenylphosphine palladium. The reaction was heated to reflux under nitrogen 30 Hfr=Imidazo 1,2-alpyridine for 16 hours. The reaction was cooled to 22 C and quenched Hfs=Imidazo 1.5-alpyridine by adding a solution of 6 g of ethylene diamine tetraacetic To a flask were added 2.0 g of 2-(aminomethyl)pyridine, acid in 40 ml water pH adjusted to 8 with aqueous sodium 0.12 g of tetrabutylammonium bromide, 5.7g of chloroform, bicarbonate. 50 ml Hexane and 20 ml ethyl acetate were and 30 ml 1,2-dimethoxyethane. While stirring under nitro added and the mixture was stirred for one hour before the 35 gen, 40 ml of 40% aqueous Sodium hydroxide was added and aqueous layer was removed and the organic layer was dried the mixture was heated to 50 C for 4.5 hours. After cooling to over sodium sulfate. After filtration and solvent removal, the 22 C, the mixture was extracted twice with ethyl acetate, and product was purified by silica gel chromatography using 5% the ethyl acetate layer was dried over sodium sulfate. After filtration and solvent removal, the product was purified by ethyl acetate in hexane to give 0.7 g clear colorless oil. silica gel chromatography using straight ethyl acetate to 5% Hea-6-Methyl-2,2'-bipyridine 40 acetonitrile in ethyl acetate resulting in a brown oil which Hec=Quinolin-8-ol crystallized on standing. The product was Sublimed to give Hee-Acetylcholine Chloride 0.36 g of a yellow solid. Heg Anthranil Hfv=Isoquinoline Heh-Benzimidazole Hfw=Lepidine Hei=Benzothiazole 45 Hfx=Lithium Acetate He=Benzoxazole Hfy=Lithium Benzoate Hen-Benzyltrimethylammonium Chloride Hfz=Lithium Bromide Heo-2,2'-Ethane-1,2-diylbis(1H-benzimidazole) Hga=Lithium Chloride To a flask were added 3 g of 1.2-phenylene diamine, 1.6 g. Hgc=Lithium Diphenylphosphinate of succinic acid, and 30 ml of 4M hydrochloric acid. The 50 To a flask were added 1.0 g diphenylphosphinic acid, 182 mixture was heated to reflux under nitrogen for 22 hours, and mg lithium hydroxide monohydrate, 10 ml of water and 30 ml then cooled to 22 C. The solid was filtered, washed with a 2-propanol. The mixture was heated to 70 C under nitrogen little water and dissolved in a warm mixture of 30 ml of until a clear solution was obtained. The mixture was cooled acetone and 40 ml of water. Enough ammonium hydroxide and the solvent was removed under reduced pressure and the was added to basify the mixture, and after cooling to 22 C, the product was slurried in a small amount of 2-propanol, filtered product was filtered and washed with 20 ml of 50% acetone and washed with 2-propanol. After drying, a white Solid was and dried, resulting in a light pink Solid. obtained. Hes=Choline chloride Hgh-Lithium Salicylate Heu-1-Pyridin-2-yl-N-(pyridin-2-ylmethyl)methanamine To a flask were added 10.0 g salicylic acid, 2.9 g lithium 60 hydroxide monohydrate, 20 ml of water and 100 ml 2-pro Hew=Dipyridin-2-ylmethanone panol. The mixture was heated to 50 C for 1.5 hours and then Hez-N,N'-Bisphenylmethylenelethane-1,2-diamine (mix cooled and the solvent was removed under reduced pressure. ture of cis/trans isomers) The product was slurried in 25 ml diethyl ether, filtered and Hfc-Diethylphenylphosphine washed with diethyl ether. After drying, 7.0 g of a white solid Hfd=2-(Diphenylphosphino)pyridine 65 was obtained. Hfe-Diphenylphosphine oxide Hgi-Lithium Trifluoroacetate Hff-Di-tert-butylphosphine oxide Hgk=N.N.N',N'-Tetramethylpropane-1,3-diamine US 7,525,717 B2 121 122 Hgm=N.N.N',N'-Tetramethylethylenediamine To a flask were added 5.0 g 2,2'-dipyridiylamine, 4.9 g of Hgp-N,N-Dipyridin-2-ylacetamide pulverized potassium hydroxide and 45 ml of N,N-dimethyl To a flask were added 2,2'-dipyridylamine and 12 ml acetic formamide. After stirring for 1 hour under nitrogen, the mix anhydride. The mixture was heated to 110C under nitrogen ture was cooled to 5 Cand 5.0 g of 1-iodopropane were added. for 5 hours and cooled to 22 C. After quenching with a slow The mixture was allowed to warm to 22 C and stirred for 5 addition of aqueous Sodium bicarbonate, the mixture was hours. After quenching with 45 ml water, the product was made basic with the addition of small portions of sodium extracted with ether and washed twice with water. Following carbonate. The product was extracted with ethyl acetate and removal of solvent, the product was purified by silica gel after removal of solvent, it was purified by silica gel chroma chromatography using 40% ethylacetate in hexane to give 4.8 tography using 65% ethyl acetate in hexane to give 0.8g of an 10 g of nearly colorless oil. oil. Hha=6-Methyl-N-(6-methylpyridin-2-yl)-N-propylpyridin Hgr=2.9-Dimethyl-1,10-phenanthroline hydrate 2-amine Hgt=N-Methyl-N-pyridin-2-ylpyridin-2-amine To a flask were added 1.0 g 2,2'-dipyridiylamine, 1.0 g of 6-Methyl-N-(6-methylpyridin-2-yl)pyridin-2-amine pulverized potassium hydroxide and 15 ml of N,N-dimethyl 15 formamide. After stirring for 1 hour under nitrogen, the mix To a flask were added 0.76 g 6-methyl-2-aminopyridine, ture was cooled to 5 C and 0.9 g of iodomethane were added. 1.0 g 2-bromo-6-methylpyridine, 0.95 g sodium tert-butox The mixture was allowed to warm to 22 C and stirred for 16 ide, 0.16 g 1,1'-bis(diphenylphosphino) ferrocene and 50 ml hours. After quenching with 15 ml water, the reaction was toluene. The mixture was purged thoroughly with nitrogen extracted twice with diethyl ether and washed with water. and 0.14 g of tris(dibenzylideneacetone)d2-propanolladium Following removal of solvent, the product was purified by (O) was added and the mixture was heated to 80 C under silica gel chromatography using 35% ethyl acetate in hexane nitrogen for 3 hours. After cooling to 22 C and quenching to give 0.16 g of an oil. with 50 ml water, the product was extracted twice with ethyl Hgu=N,6-Dimethyl-N-pyridin-2-ylpyridin-2-amine acetate and washed twice with water. After filtration and solvent removal, the product was dissolved in 50 ml tert-butyl To a flask were added 0.75 g 2-(methylamino)pyridine, 1.0 25 methyl ether and extracted into 60 ml 1M hydrochloric acid. g 2-bromo-6-methylpyridine, 0.95 g sodium tert-butoxide, Methanol was added and the mixture was heated to dissolve 0.16 g 1,1'-bis(diphenylphosphino) ferrocene and 50 ml tolu the solids and the organic layer was removed. The aqueous ene. The mixture was purged thoroughly with nitrogen and layer was basified with 3M sodium hydroxide solution, the 0.14 g of tris(dibenzylideneacetone)d2-propanolladium(0) product was extracted with tert-butyl methyl ether and was added and the mixture was heated to 80C under nitrogen 30 washed with water. Following removal of solvent, an oil was for 16 hours. After cooling to 22 C and quenching with 50 ml obtained that was carried directly into the next step. water, the product was extracted twice with ethyl acetate and washed twice with water. After filtration and solvent removal, 6-Methyl-N-(6-methylpyridin-2-yl)-N-propylpyri the product was purified by silica gel chromatography using din-2-amine 35% ethyl acetate in hexane resulting in an orange oil. This 35 was dissolved in 75 ml tert-butyl methyl ether and extracted To a flask were added 1.0 g 6-methyl-N-(6-methylpyridin into 75 ml 1M hydrochloric acid. 2-yl)pyridin-2-amine, 0.84 g of pulverized potassium After basification with 3M sodium hydroxide solution, the hydroxide and 15 ml of N,N-dimethylformamide. After stir product was extracted with 75 ml tert-butyl methyl ether. ring for 1 hour under nitrogen, the mixture was cooled to 5 C Following removal of solvent, 1.1 g of a yellow oil was 40 and 0.85g of 1-iodopropane were added. The mixture was obtained. allowed to warm to 22 C and stirred for 16 hours. After Hgw=N-Octadecyl-N-pyridin-2-ylpyridin-2-amine quenching with 15 ml water, the product was extracted twice To a flask were added 1.0 g 2,2'-dipyridylamine, 1.0 g of with diethyl ether and washed with water. Following removal pulverized potassium hydroxide and 15 ml of N,N-dimethyl of solvent, the product was purified by silica gel chromatog formamide. After stirring for 1 hour under nitrogen, the mix 45 raphy using 10% ethyl acetate in hexane to give 11.0 g of a ture was cooled to 5 C and 2.2 g of 1-iodooctadecane were colorless oil. added. The mixture was allowed to warm to 22 C and stirred Hhb-N,N-Bis(pyridin-2-ylmethyl)propan-1-amine for 16 hours, then heated to 40C for 2 hours. After quenching To a flask were added 1.0 g di-(2-picolyl)amine, 0.85g of with 25 ml water and cooling to 22 C, the product was filtered pulverized potassium hydroxide and 15 ml of N,N-dimethyl and washed with water. The product was dissolved in 25 ml 50 formamide. After stirring for 1 hour under nitrogen, the mix hot ethanol with 100 mg activated carbon, stirred for 30 ture was cooled to 5 Cand 1.7g of 1-iodopropane were added. minutes and filtered through celite. After adding 25 ml water The mixture was heated to 35 Cand stirred for 16 hours. After and cooling to 5 C, the product was filtered, washed with quenching with 30 ml water, the product was extracted with water and dried leaving 2.1 g light yellow solid. ethyl acetate and washed twice with water. Following Hgx=N-Phenyl-N-pyridin-2-ylpyridin-2-amine 55 removal of solvent, the product was purified by silica gel To a flask were added 0.5g aniline, 2.1 g 2-bromopyridine, chromatography using ethyl acetate to give 0.65g of a yellow 1.3 g sodium tert-butoxide, 0.15 g 1,1'-bis(diphenylphos oil. phino) ferrocene and 50 ml toluene. The mixture was purged Hhc=1-Propyl-4-pyridin-4-ylpyridinium iodide thoroughly with nitrogen and 0.12 g of tris(dilbenzylideneac To a flask were added 1.0 g 4,4'-dipyridyl, 1.07 g 1-io etone)d2-propanolladium(0) was added and the mixture was 60 dopropane and 5 g acetonitrile and the mixture was allowed to heated to 80C under nitrogen for 48 hours. After cooling to 22 stand at 22 C for 2 months. The liquid was decanted away C most of the solvent was removed and the mixture was taken from the solid and the solid was dissolved in 15 ml hot up in 100 ml ethyl acetate and filtered. Following solvent acetonitrile. After hot filtration, the solution was cooled to 5C removal, the product was purified by silica gel chromatogra and filtered. After washing with acetonitrile, the product was phy using 50% ethyl acetate in hexane resulting in 0.62 g of 65 dried leaving 0.8 g. red-orange Solid. oil which crystallized on standing. Hhd=Phenoxathiin HgZ-N-Propyl-N-pyridin-2-ylpyridin-2-amine Hhh-Poly(2-vinylpyridine) US 7,525,717 B2 123 124 Hhj=Potassium O,O-diethylthiophosphate To a flask were added 1.0 g diphenylphosphinic acid, 3.2g Hhl=Quinaldine of a 20% solution of tetraethylammonium hydroxide in water Hhv=Sodium Iodide and 20 ml 2-propanol. After heating to 50 C under nitrogen Hif–Tetrabutylammonium 3.5-Bis(trifluoromethyl)phenox for 1 hour, the solvent was removed and another 20 ml of ide 5 2-propanol were added and removed by distillation under To a flask were added 11.0 g 3,5-bis(trifluoromethyl)phe reduced pressure. After drying, an oil was obtained. nol, 1.8 g of a 55-60% solution of tetrabutylammonium Hig-Tetraethylammonium Iodide hydroxide in water and 10 ml 2-propanol. After heating to 50 Hjr-Tris(4-fluorophenyl)phosphine C under nitrogen for 1 hour, the solvent was removed and His–Tris(4-methoxyphenyl)phosphine another 10 ml of 2-propanol were added and removed by 10 Hit=Tris(2-methylphenyl)phosphine distillation under reduced pressure. An oil was obtained Hju=Tris(4-methylphenyl)phosphine which crystallized on Standing. Hjx-Tributylphosphine oxide Hii-Tetrabutylammonium Bis(hydroxymethyl)phosphinate Hy=Tricyclohexylphosphine To a flask were added 0.48 g bis(hydroxymethyl)phos Hka-Triethylphosphine sulfide phinic acid, 1.6 g of a 55-60% solution of tetrabutylammo 15 Hke=Triphenylphosphine nium hydroxide in water and 10 ml 2-propanol. After heating Hkf-Triphenylphosphine oxide to 50 C under nitrogen for 1 hour, the solvent was removed Hkh-Triphenylphosphite and another 10 ml of 2-propanol were added and removed by Hna-Thiazolo 2,3-bbenzimidazole-3 (2H)-one distillation under reduced pressure. An oil was obtained. Hnd=1,2,4-Triazolo 1.5-alpyrimidine Hij=Tetrabutylammonium Bromide Hnf2-Mercaptobenzothiazole Hik-Tetrabutylammonium Chloride Hng Tribenzylphosphine Hil–Tetrabutylammonium Di(4-Methoxyphenyl)phosphi Hnh-Benzyl (diphenyl)phosphine nate Hnm=N,N-Bis(1-methyl-1H-benzimidazol-2-yl)methyl To a flask were added 2.0 g bis(4-methoxyphenyl)phos butanamine phinic acid, 3.0 g of a 55-60% solution of tetrabutylammo 25 2-(Chloromethyl)-1-methyl-1H-benzimidazole nium hydroxide in water, 2.0 g of water and 18ml 2-propanol. After heating to 50 C under nitrogen for 1 hour, the solvent To a pressure reaction bottle was added 4 g N-methyl-2- was removed and another 20 ml of 2-propanol were added nitroaniline, 0.44 g 5% palladium on carbon, and 100 ml and removed by distillation under reduced pressure. A waxy ethanol. The mixture was hydrogenated at 22 C and 40 psi solid was obtained. 30 hydrogen for 2 hours. Following filtration through celite, and Him=Tetrabutylammonium Dibenzoylmethanate solvent removal, a dark red oil was obtained. To this oil was To a flask were added 3.0 g dibenzoylmethane, 5.7g of a added 3.7 g chloroacetic acid and 40 ml 5M hydrochloric 55-60% solution of tetrabutylammonium hydroxide in water acid. After refluxing under nitrogen for 2.5 hours, the mixture and 20 ml 2-propanol. After heating to 50 C under nitrogen was cooled to 22 C, diluted with 200 ml water, and neutralized for 1 hour, the solvent was removed and another 20 ml of 35 with solid sodium bicarbonate. The resulting solid was fil 2-propanol were added and removed by distillation under tered, washed with water and dried giving 3.7 g gray solid. reduced pressure. After drying the product, a yellow solid was N,N-Bis(1-methyl-1H-benzimidazol-2-yl)methyl obtained. butanamine Hin–Tetrabutylammonium Dimethylolpropionate To a flask were added 3.0 g 2.2-bis(hydroxymethyl)propi 40 To a flask were added 2.0 g 2-(chloromethyl)-1-methyl onic acid, 9.5g of a 55-60% solution of tetrabutylammonium 1H-benzimidazole and 40 ml N,N-dimethylformamide. 0.41 hydroxide in water and 40 ml 2-propanol. After heating to 50 g Butylamine were added dropwise followed by dropwise C under nitrogen for 1 hour, the solvent was removed and addition of 1.2 g of triethylamine. The reaction mixture was another 40 ml of 2-propanol were added and removed by heated to 50 C under nitrogen for 16 hours, and then cooled to distillation under reduced pressure. After drying, a pale yel 45 22 C. After dilution with 100 ml water, the solid was filtered low oil was obtained. and washed with water. The wet cake was dissolved in 20 ml Hio-Tetrabutylammonium Dimethylphosphinate of hot ethanol and 15 ml water was added. After cooling to 5 To a flask were added 11.0 g dimethylphosphinic acid, 4.5 C, the solid was filtered and washed with 33% ethanol. The g of a 55-60% solution of tetrabutylammonium hydroxide in wet cake was dissolved in 15 ml of hot ethanol and 10 ml water and 20 ml 2-propanol. After heating to 50 C under 50 water was added. After cooling to 5 C, the solid was filtered and washed with 33% ethanol. The product was then purified nitrogen for 1 hour, the solvent was removed and another 20 by silica gel chromatography using 5% methanol in ethyl ml of 2-propanol were added and removed by distillation acetate to 10% methanol in ethyl acetate giving 0.93 g of a under reduced pressure. After drying, a yellow partially white solid. solidified product was obtained. Hnr-2,2'-Methylenebis(1H-benzimidazole) Hir-Tetrabutylammonium Iodide 55 To a flask were added 5 g of 1.2-phenylene diamine, 2.4g Hit-Tetrabutylammonium Methylphenylphosphinate of malonic acid, and 20 g of polyphosphoric acid. The mix To a flask were added 2.0 g methylphenylphosphinic acid, ture was heated to 180C under nitrogen for 4 hours, and then 5.4 g of a 55-60% solution of tetrabutylammonium hydroxide cooled to 150 C. After the addition of 40 ml of water, the in water and 25 ml 2-propanol. After heating to 50 C under mixture was cooled to 22 C and neutralized with aqueous nitrogen for 1 hour, the solvent was removed and another 20 60 ammonium hydroxide. The solid was filtered and washed ml of 2-propanol were added and removed by distillation with water. After triturating the product in 200 ml of hot under reduced pressure. After drying, an oil was obtained. acetonitrile, the mixture was cooled to 22 C, filtered, washed Hiu-Tetrabutylammonium Nitrate with acetonitrile, and dried resulting in 2.7 g of a gray Solid. Hja=Tetrabutylammonium Thiocyanate Hns=Indazole Hjd=Tetrabutylphosphonium Bromide 65 Hnt-N'-[2-(Diethylamino)ethyl-N,N-diethylethane-1,2-di Hje–Tetraethylammonium Chloride Monohydrate amine Hjf-Tetraethylammonium Diphenylphosphinate Hnu=2,2'-(1,3-Phenylene)bis(1-methyl-1H-benzimidazole) US 7,525,717 B2 125 126 To a Pressure reaction bottle was added 2.5g of N-methyl To a Pressure reaction bottle was added 3.5g of N-methyl 2-nitroaniline, 0.3 g 5% palladium on carbon, and 65 ml 2-nitroaniline, 0.25 g 5% palladium on carbon, and 70 ml ethanol. The mixture was purged with hydrogen and then ethanol. The mixture was purged with hydrogen and then hydrogenated under 40 psi hydrogen for 1 hour. The catalyst hydrogenated under 40 psi hydrogen for 1.5 hours. The cata was filtered off on a bed of celite. The solvent was removed 5 lyst was filtered off on a bed of celite. The solvent was and to the resulting red oil was added 70g of polyphosphoric removed and to the resulting red oil was added 2.9 g of acid and 1.4 g of isophthalic acid. The reaction mixture was salicylic acid, and a solution of 8 g of phosphorus pentoxide heated to 200 C under nitrogen for 3 hours, and then cooled to 150 C. After dilution with 150 ml water, the mixture was in 80 g of methanesulfonic acid. The reaction mixture was basified with sodium hydroxide. The solid was filtered, heated to 10°C. under nitrogen for 16 hours, and then cooled washed with water, and then dissolved in 40 ml of hot metha 10 to 22 C. After dilution with 300 ml of cold water, the mixture nol with 140 mg of activated carbon. After filtration of the was neutralized with sodium hydroxide. After extraction with activated carbon, enough water was added to turn the Solution ethyl acetate and filtration, the solvent was removed leaving cloudy, and the mixture was decanted away from a dark oil. an oil which partially crystallized on standing. After dissolv After cooling to 5 C, more water was added causing a pre ing the product in hot 2-propanol and filtering hot, the solu cipitate which was filtered and washed with water. The solid 15 tion was cooled to 5 C, filtered, and washed with 2-propanol. was dissolved in 26 ml of 2-propanol, filtered hot, and 10 ml The product was purified by silica gel chromatography using of water were added. a gradient from 80% ethyl acetate in hexane to straight ethyl After cooling to 10 C, the solid was filtered, washed with acetate, resulting in 1.5 g of a tan Solid. 50% 2-propanol, and dried, resulting in 1.1 g of an off-white Hon=2,2'-Propane-2,2-diylbis(1-pentyl-1H-benzimidazole) solid. 2.8 g. 2,2'-Propane-2,2-diylbis(1H-benzimidazole) was Hnv=3-Methylbenzothiazole-2-thione added to 60 ml of N,N-dimethylformamide. 1.21 g Ofa 60% Hnw=1-Methyl-1H-benzimidazol-2-thiol Sodium hydride dispersion in mineral oil was added in por Hof-N-(Pyridin-2-ylmethyl)pyridin-2-amine tions. 6.0 g of 1-iodopentane was added and the mixture was To a flask were added 4.7 g of 2-aminopyridine, 5.35 g of stirred under nitrogen. After 4 hours, the reaction was 2-pyridinecarboxaldehyde, and 75 ml toluene. The flask was 25 quenched with 160 ml of water and then extracted with two 75 equipped with a Dean-Stark trap and heated to reflux under ml portions of ethyl acetate/methanol (-99:1, v/v). The com nitrogen. After 16 hours, the toluene was removed and 100 ml bined organic layers were washed twice with 75 ml of water. ethanol were added followed by 2.1 g of sodium borohydride. The cloudy organic layer was filtered. Following solvent The mixture was stirred at 22 Cunder nitrogen for 1 hour, and removal to give a brown oil, the product was purified by silica then 50 ml of water were added slowly. Following removal of 30 gel chromatography increasing from 25% to 50% ethyl the ethanol, aqueous ammonium chloride was cautiously acetate in hexane by volume over the course of the elution. added resulting in gas evolution. The product was extracted 3.46 g of a yellow oil was obtained. twice with 50 ml ethyl acetate and washed with 30 ml water. Hra=2,2'-Methylenebis(1-benzyl-1H-benzimidazole) After solvent removal, the product was purified by silica gel To a flask were added 2.0 g 2,2'-methylenebis(1H-benz chromatography using 5% methanol in ethyl acetate resulting 35 imidazole), 2.8 g. potassium carbonate, 100 ml N,N-dimeth in an orange oil. ylformamide and the mixture was stirred under nitrogen. 2.5 Hog 2-Mercaptobenzimidazole gbenzyl chloride were added and the mixture was heated to Hos-2-Benzylpyridine 70 C for 16 hours. Another 0.7 g benzyl chloride was added Hou-N-Ethyl-N-(pyridin-2-ylmethyl)pyridin-2-amine and the reaction was heated to 70 C for another 20 hours. The To a flask were added 2.5 g N-(pyridin-2-ylmethyl)pyri 40 reaction was cooled to 22 C. quenched with 150 ml water and din-2-amine and 40 ml N,N-dimethylformamide, and the the product was extracted with ethyl acetate and washed with mixture was cooled to 5 C. To this mixture was added 0.65g water. Following removal of solvent, the product was recrys of 60% sodium hydride in mineral oil in small portions, and after stirring at 5-10C for ten minutes, 2.2 g of diethylsulfate tallized from 10 ml ethanol, then 10 ml acetonitrile with 1 ml were added. The reaction mixture was heated to 45 C for 16 of water. The product was filtered and dried resulting in 0.67 hours, then cooled to 22 C and quenched with 40 ml water. 45 gtan Solid. The product was extracted twice with 40 ml hexane and Hrb-2,2'-Ethane-1,2-diylbis(1-benzyl-1H-benzimidazole) following removal of the solvent, the product was purified by To a flask were added 0.5 g 2,2'-ethane-1,2-diylbis(1H silica gel chromatography using a gradient from 50% ethyl benzimidazole), 0.7 g potassium carbonate, 30 ml N,N-dim acetate, 49% hexane and 1% methanol to 60% ethyl acetate, ethylformamide and the mixture was stirred under nitrogen. 39% hexane, and 1% methanol resulting in 1.4 g of a yellow 50 0.6 g Benzyl chloride were added and the mixture was heated oil. to 60 C for 16 hours. Another 0.5 g benzyl chloride were Hoz-N-(2-Ethylphenyl)-N-pyridin-2-ylpyridin-2-amine added and the reaction was heated to 70 C for another 20 To a flask were added 4.0 g of 2-ethylaniline, 10.7 g of hours and then cooled to 22 C. The reaction was quenched 2-bromopyridine, 7.9 g of sodium tert-butoxide, and 165 ml with 30 ml water and the product was filtered and washed with toluene. The mixture was purged thoroughly with nitrogen 55 water. The product was re-slurried in 80 ml hot acetonitrile, and 205 mg of 2,2'-bis(diphenylphosphino)-1,1'-binaphtha cooled, filtered and dried resulting in 0.35g of a white solid. lenehthalene and 74 mg of palladium acetate were added. The Hrc=2,2'-Methylenebis(1,3-benzothiazole) reaction mixture was heated to 75 C for 16 hours, and then To a flask were added 50 g polyphosphoric acid. After cooled to 22 C. After quenching with 100 ml water, the heating to 70 C under nitrogen, a mixture of 3.13 g 2-ami product was extracted with 100 ml ethyl acetate, and washed 60 nothiophenol and 1.3 g malonic acid was added. The reaction with 50 ml water. Following solvent removal, the product was mixture was heated to 135C for 1 hour, then 145 C for 1 hour. purified by silica gel chromatography using a gradient from After cooling to 70 C, the mixture was poured into 100 ml 25% ethyl acetate in hexane to 50% ethyl acetate in hexane, water. The slurry was cooled to 22 C, filtered and the solid was resulting in 7.5 g of a yellow solid. washed with water. The solid was added to 50 ml ethanol and Hpg=2,6-Pyridinedicarboxamide 65 basified with aqueous ammonium hydroxide. After cooling to Hp=2-(1H-Pyrazol-3-yl)phenol 5 C, the solid was filtered and washed with water. The solid Hpo-2-(1-Methyl-1H-benzimidazol-2-yl)phenol was dissolved in 14 ml hot ethanol and 7 ml water was added US 7,525,717 B2 127 128 and the solution was cooled to 5 C. Following filtration, the 22 C and quenched with 100 ml water. The product was white solid was washed with 50% ethanol and dried, leaving extracted twice with 50 ml ethyl acetate and following 1.1 g. removal of the solvent, the product was purified by silica gel Hrg-Tetrabutylammonium Diisobutyldithiophosphinate chromatography using a gradient from 100% hexane to 25% To 40 ml of 2-propanol, 3.63 g diisobutyldithiophosphinic ethyl acetate in hexane. An oil was obtained that crystallized acid and 7.34 g of 55-60% by weight tetrabutylammonium on standing which was dried resulting in 4.2 g of a white solid. hydroxide in water were added. The mixture was stirred under nitrogen for one hour. The solvent was removed by distilla 1-Ethyl-N-methyl-N-pyridin-2-yl-1H-benzimidazol tion. To remove residual water, 2-propanol was twice added 2-amine and subsequently removed by distillation. The liquid was 10 cooled to less than OC for 16 hours. To the precipitates that To a flask were added 11.0 g of 2-bromo-1-ethyl-1H-ben formed, a small amount of hexane was added to give a slurry. Zimidazole, 0.482-(methylamino)pyridine, 0.64 g of sodium The slurry was filtered, washed with hexane, and dried under tert-butoxide, and 25 ml toluene. The mixture was purged reduced pressure yielding 6.07 g of a white solid. thoroughly with nitrogen and 250 mg of 2,2'-bis(diphe Hri-N,N-Bis(pyridin-2-ylmethyl)pentan-1-amine 15 nylphosphino)-1,1'-binaphthalene and 64 mg of palladium To 15 ml of N,N-dimethylformamide, 0.85g potassium acetate were added. The reaction mixture was heated to 90 C hydroxide, 1.0 g di(2-picolyl)amine, and 0.99g 1-iodopen for 16 hours, and then cooled to 22 C. After quenching with 50 tane were successively added. The mixture was stirred under ml water, the product was extracted with 20 ml ethyl acetate. nitrogen at 35 C for 2.5 hours before an additional 0.99g The product was extracted with 30 ml of 1M hydrochloric 1-iodopentane were added. The mixture was then stirred for acid, and then basified with 3M sodium hydroxide. Following 16 hrs at 35 C under nitrogen. The reaction was quenched extraction with 20 ml ethyl acetate, the product was purified with 90 ml of water and extracted with two 50 ml portions of by silica gel chromatography using a gradient from 40% ethyl ethyl acetate. The combined organic layers were washed with acetate in hexane to 70% ethyl acetate in hexane, resulting in two 25 ml portions of water, dried over anhydrous magnesium 0.6 g of a yellow oil which crystallized on standing. The Sulfate, and filtered. Following solvent removal, the orange 25 product was recrystallized from a mixture of 5 ml hexane with oil obtained was purified by silica gel chromatography using 1.5 ml 2-propanol. After filtration and drying of the product, a methanol/ethyl acetate mixed solvent system that was a 0.44 g of a yellow solid was obtained. ramped from 0% to 10% methanol by volume during the Hrz 2,2-Dimethyl-N,N-dipyridin-2-ylpropanamide course of the elution. An orange oil (0.98 g) was obtained. To a flask were added 2.0 g of 2,2'-dipyridylamine and 35 Hrk=1-(Chloromethyl)-4-aza-1-azoniabicyclo[2.2.2]octane 30 ml of acetonitrile. The Solution was stirred under nitrogen and bromide cooled to 5 C, when 1.5 g of triethylamine were added, 20 ml Ofacetone, 4.0 g of 1,4-diazabicyclo[2.2.2]octane, followed by 1.5g of trimethylacetylchloride and the mixture and 20 ml of bromochloromethane, were added to a flask, was allowed to warm to 22 C. After 1 hour, 50 ml of water capped, and stirred at room temperature. Within 45 minutes were added and the acetonitrile was removed. The product white precipitate had formed. After 3.5 hours the mixture was 35 was extracted with ethyl acetate and washed with water. Fol cooled to 0-5C, filtered, washed with three 10 ml portions of lowing solvent removal, the product was purified by silica gel cold acetone, and dried under reduced pressure overnight. chromatography using 50% ethyl acetate in hexane, resulting 2.31 g Ofa white solid was obtained. in 1.8g of an oil that solidified on standing. Hrl=N-Methylpyridin-2-amine Hsc=2,2-Dimethyl-N-(6-methylpyridin-2-yl)-N-pyridin-2- Hrm=Tetraphenylphosphonium Iodide 40 ylpropanamide Hry=1-Ethyl-N-methyl-N-pyridin-2-yl-1H-benzimidazol-2- To a flask were added 1.06 g of di-(2-picolyl)amine and 20 amine ml of acetonitrile. The solution was stirred under nitrogen, when 0.7 g of triethylamine were added, followed by 1.5g of 2-Bromo-1H-benzimidazole trimethylacetyl chloride. After 1 hour, 20 ml of water were 45 added and the acetonitrile was removed. The product was To a flask were added 24 ml 48% hydrobromic acid and 120 extracted with ethyl acetate and washed with water. Follow ml methanol. The mixture was cooled to 5C and 10g 2-mer ing solvent removal, the product was recrystallized by dis captobenzimidazole was added. Maintaining a temperature solving in 6 ml hot hexane with 0.5 ml 2-propanol. Another 2 of less than 10 C, 41.5 g of bromine were added in small ml hexane were added and the mixture was cooled to 5 C, portions. The mixture was allowed to warm to 22 C, and 50 filtered, washed with hexane and dried, resulting in 1.3 g of an stirred for 16 hours under nitrogen. After cooling to 5 C, the off-white solid. solid was filtered and then added to 50 ml methanol contain Hss=6-methyl-N-phenyl-N-pyridin-2-ylpyridin-2-amine ing 20 ml aqueous ammonium hydroxide. The pH was adjusted to 6.5 with acetic acid, and the mixture was cooled to 6-Methyl-N-phenylpyridin-2-amine 5 C. The product was filtered and washed with water, and 55 dried. A second crop was obtained by cooling the filtrates To a flask were added 2.2 g of 2-amino-6-methylpyridine, which was filtered, washed with water and dried. The com 3.1 g of bromobenzene, 2.7 g of sodium tert-butoxide, and 50 bined crops resulted in 9.05 g of a solid. ml toluene. The mixture was purged thoroughly with nitrogen and 62 mg of 2,2'-bis(diphenylphosphino)-1,1'-binaphthale 2-Bromo-1-ethyl-1H-benzimidazole 60 nehthalene and 22 mg of palladium acetate were added. The reaction mixture was heated to 10° C. for 16 hours, and then To a flask were added 4 g 2-bromo-1H-benzimidazole and cooled to 22 C. After quenching with 50 ml water, the product 60 ml tetrahydrofuran, and the mixture was cooled to 10C. To was extracted with 20 ml ethyl acetate, and washed with 15 ml this mixture was added 1.2 g of 60% sodium hydride in water. The product was extracted with 50 ml of 1M hydro mineral oil in small portions, and after stirring at 10 C for ten 65 chloric acid, and then basified with aqueous ammonium minutes, 4.7 g of diethyl sulfate were added. The reaction hydroxide. Following extraction with 20 ml ethyl acetate, the mixture was heated to 40C for several hours, then cooled to product was purified by silica gel chromatography using a US 7,525,717 B2 129 130 gradient from 10% ethyl acetate in hexane to 15% ethyl Htm=N.N.N',N'.2.2-Hexamethylpropane-1,3-diamine acetate in hexane, resulting in 1.3 g of a yellow-orange oil. Hto=6-Methyl-N-pyridin-2-ylpyridin-2-amine To a flask were added 3.2 g of 2-amino-6-methylpyridine, 6-Methyl-N-phenyl-N-pyridin-2-ylpyridin-2-amine 4.9 g of 2-bromopyridine, 3.5g of sodium tert-butoxide, and 120 ml toluene. The mixture was purged thoroughly with To a flask were added 18.4 g of 6-methyl-N-phenylpyridin nitrogen and 83 mg of 1,1'-bis(diphenylphosphino) ferrocene 2-amine, 15.8 g of 2-bromopyridine, 11.5g of sodium tert and 34 mg of palladium acetate were added. The reaction butoxide, and 250 ml toluene. The mixture was purged thor mixture was heated to 65 C for 3 hours, to 75 C for 2 hours, oughly with nitrogen and 270 mg of 1,1'-bis and then cooled to 22 C. After quenching with 75 ml of water, (diphenylphosphino)ferrocene and 110 mg of palladium 10 the product was extracted with 75 ml ethyl acetate. The prod acetate were added. The reaction mixture was heated to 90 C uct was extracted with 50 ml of 1M hydrochloric acid, and for 6 hours, and then cooled to 22 C. After quenching with 100 washed with 30 ml of ethyl acetate. After basifying with 3M ml water, the product was extracted with 75 ml ethyl acetate. sodium hydroxide, the product was extracted with 75 ml of The product was extracted with 50 ml of 1M hydrochloric ethyl acetate and washed with 30 ml of water. Following acid, and then basified with sodium hydroxide. The mixture 15 Solvent removal, the product was purified by silica gel chro was cooled to 5 C, and the crude product was filtered and matography using 38% ethyl acetate, 50% hexane, and 12% washed with water. The product was dissolved in 100 ml hot methanol resulting in an orange oil. 2-propanol and treated with 0.4 g activated carbon. After hot Htp=PP-Diphenyl-N,N-dipyridin-2-ylphosphinous amide filtration through a bed of celite, 150 ml of water was added HitcN-(1-Methyl-1H-benzimidazol-2-yl)methyl-N-pyri slowly and the mixture was seeded to induce crystallization. din-2-ylpyridin-2-amine After cooling to 5 C, the product was filtered and washed with To a flask were added 1.1 g of 2,2'-dipyridylamine and 25 50 ml of 33% 2-propanol in water. The product was dried ml of N,N-dimethylformamide. To this mixture were added resulting in 21 g of a light tan Solid. 0.32g of 60% sodium hydride in mineral oil in small portions, Hst-N-Pyridin-2-yl-N-(pyridin-2-ylmethyl)pyridin-2- and after stirring at 10 C for ten minutes, 1.2 g of 2-(chlorom amine 25 ethyl)-1-methyl-1H-benzimidazole in 5 ml of N,N-dimethyl To a flask were added 5.2 g pulverized potassium hydrox formamide were added. The reaction mixture was stirred at ide and 35 ml dimethylsulfoxide. After adding 3.4 g 2,2'- 22 C for several hours, and then quenched with 40 ml water. dipyridylamine, the mixture was stirred under nitrogen for 45 The product was extracted with 50 ml ethyl acetate, and then minutes, when 3.3 g 2-(chloromethyl)pyridine hydrochloride extracted with 30 ml of 1M hydrochloric acid, and basified was added. After stirring for 1 hour, 100 ml of water was 30 with 3M sodium hydroxide. Following extraction with 20 ml added and the product was extracted with 60 ml of 50% ethyl ethyl acetate, the product was purified by Silica gel chroma acetate, 50% hexane. The organic layer was washed with 30 tography using 33% ethyl acetate, 62% hexane, and 5% ml water and the solvent was removed. The residue was added methanol, resulting in an oil which crystallized on Standing. to 5 ml hot ethanol, and 20 ml of water was added. After After drying, 0.6 g of a yellow solid remained. cooling to 5 C, the solid was filtered and washed with water. 35 Hui-6-Methyl-N-(6-methylpyridin-2-yl)methyl-N-pyri The product was dissolved in 20 ml hot ethanol and treated din-2-ylpyridin-2-amine with 150 mg activated carbon. After hot filtration through celite, 40 ml of water were added and the mixture was cooled 2-(Bromomethyl)-6-methylpyridine to 5 C. The product was filtered, washed with 20 ml 20% ethanol in water, and dried resulting in 2.9 g of an off-white 40 To a flask containing a mixture of 15 ml of 48% hydrobro solid. mic acid and 11 ml of sulfuric acid was added 5g of 6-methyl HSZ-N-(6-Methylpyridin-2-yl)methyl-N-pyridin-2-ylpyri 2-pyridinemethanol dropwise under nitrogen. The mixture din-2-amine was heated to 90C for 4 hours, and poured into 25 ml of water. To a flask were added 0.6 g pulverized potassium hydrox After neutralization with sodium carbonate, the product was ide and 15 ml dimethylsulfoxide. After adding 1.4 g of 2,2'- 45 extracted with 100 ml ethyl acetate and washed with 30 ml of dipyridylamine, the mixture was stirred under nitrogen for 45 water. Following solvent removal, the product was purified by minutes, when 1.5 g. 6-methyl-2-(bromomethyl)pyridine was silica gel chromatography using 25% ethyl acetate in hexane, added. After stirring for 1 hour, 35 ml of water was added and resulting in 6.3 g of a pink oil which Solidified on storage at -5 the product was extracted with 60 ml of 50% ethyl acetate, C. 50% hexane. The organic layer was washed with 30 ml water 50 and the solvent was removed. The residue was purified by 6-Methyl-N-(6-methylpyridin-2-yl)methyl-N-pyri silica gel chromatography using 48% ethyl acetate, 48% hex din-2-ylpyridin-2-amine ane, and 4% methanol resulting in 2.0 g of an oil. Htd=2-Pyridin-2-ylethanamine To a flask were added 1.7g pulverized potassium hydrox Htk=N-Methyl-N-(1-methyl-1H-benzimidazol-2-yl)me 55 ide and 15 ml dimethylsulfoxide. After adding 1.5 g. 6-me thylpyridin-2-amine thyl-2,2'-dipyridylamine, the mixture was stirred under nitro To a flask were added 0.6 g 2-(methylamino)pyridine and gen for 45 minutes, when 1.6 g 2-(bromomethyl)-6- 20 ml tetrahydrofuran, and the mixture was cooled to 5 C. To methylpyridine was added. After stirring for 1 hour, 35 ml of this mixture were added 0.26 g of 60% sodium hydride in water was added and the product was extracted with 60 ml of mineral oil in small portions, and after stirring at 5-10 C for 60 50% ethyl acetate, 50% hexane. The organic layer was ten minutes, 1.0 g of 2-(chloromethyl)-1-methyl-1H-benz washed with 30 ml water and the solvent was removed. The imidazole was added. The reaction mixture was heated to 45 residue was purified by silica gel chromatography using 48% C for 16 hours, then cooled to 22 Cand quenched with 40 ml ethyl acetate, 48% hexane, and 4% methanol resulting in 1.95 water. The product was extracted with 40 ml ethyl acetate and g of a yellow oil. following removal of the solvent, the product was purified by 65 Huj-N-(6-Methylpyridin-2-ylmethyl)pyridin-2-amine silica gel chromatography using 63% ethyl acetate, 25% hex To a flask were added 1.9 g of 2-aminopyridine, 2.4 g of ane and 12% methanol resulting in 0.55g of a yellow solid. 6-methyl-2-pyridinecarboxaldehyde and 45 ml toluene. The US 7,525,717 B2 131 132 flask was equipped with a Dean-Stark trap and heated to purified by silica gel chromatography using 50% ethyl reflux under nitrogen. After 16 hours, the toluene was acetate, 50% hexane, and 0.1% triethylamine resulting in 3.0 removed and 40 ml ethanol were added followed by 0.83 g of g of a light yellow oil. sodium borohydride. The mixture was stirred at 22 C under Hvo=6-Methyl-N-(6-methylpyridin-2-yl)-N-pyridin-2-ylpy nitrogen for 1 hour, and then 30 ml of water were added ridin-2-amine slowly. Following removal of the ethanol, 60 ml 1M hydro chloric acid was added cautiously, and the aqueous layer was 6-Methyl-N-(6-methylpyridin-2-yl)pyridin-2-amine washed with 20 ml ethyl acetate. After basifying with aque ous ammonium hydroxide, the product was extracted with 50 To a flask were added 3.1 g of 2-amino-6-methylpyridine, ml ethyl acetate and the solvent was removed. The product 10 5.0 g of 2-bromo-6-methylpyridine, 3.6 g of sodium tert was purified by silica gel chromatography using 74% ethyl butoxide, and 150 ml toluene. The mixture was purged thor acetate, 24% hexane, and 2% methanol resulting in 1.5g of a oughly with nitrogen and 160 mg of 1,1'-bis(diphenylphos yellow oil that solidified on standing. phino) ferrocene and 65 mg of palladium acetate were added. Hur-Potassium hydrotris(3,5-dimethylpyrazol-1-yl)borate The reaction mixture was heated to 80C for 3 hours, and then HVm=6-Methyl-N,N-dipyridin-2-ylpyridin-2-amine 15 cooled to 22 C. After quenching with 100 ml of water, the To a flask were added 3.7 g of 6-methyl-N-pyridin-2-ylpy product was extracted with 75 ml ethyl acetate. The product ridin-2-amine, 9.4 g of 2-bromopyridine, 2.0 g of sodium was extracted with 75 ml of 1M hydrochloric acid, and then carbonate, 0.05 g of copper bronze, 0.01 g of potassium basified with 3M sodium hydroxide. Following extraction bromide, and 5 ml of mesytylene. After stirring under nitro with 75 ml of ethyl acetate and washing with 30 ml of water, gen at 160C for 10 hours, the mixture was cooled to 22 C, and the solvent was removed. The product was purified by dis 35 ml of water was added and the product was extracted with Solving in a minimum amount of hot 2-propanol, and after 75 ml ethyl acetate. After washing twice with 30 ml of water, cooling to 5 C, the product was filtered, washed with cold the solvent was removed, and the product was purified by 2-propanol, and dried, resulting in 3.3 g of a tan Solid. silica gel chromatography using 75% ethyl acetate, 25% hex ane, and 0.01% triethylamine resulting in 3.2 g of a yellow oil. 25 6-Methyl-N-(6-methylpyridin-2-yl)-N-pyridin-2- Hvn=2-Methyl-N-(6-methylpyridin-2-yl)-N-pyridin-2- ylpyridin-2-amine ylquinolin-8-amine To a flask were added 2.0 g of 6-methyl-N-(6-methylpyri 2-Methylduinolin-8-amine din-2-yl)pyridin-2-amine, 4.7 g of 2-bromopyridine, 1.6 g of 30 Sodium carbonate, 51 mg of copper bronze, 5 mg of potas To a Pressure reaction bottle was added 5.0 g of 8-nitro sium bromide, and 3 ml of mesytylene. After stirring under quinaldine, 0.5g 5% palladium on carbon, and 150 ml etha nitrogen at 160 C for 16 hours, the mixture was cooled to 22 nol. The mixture was purged with hydrogen and then hydro C, and 35 ml of water was added and the product was genated under 40 psi hydrogen for 16 hours. The catalyst was extracted with 50 ml ethyl acetate. After washing twice with filtered off on a bed of celite. The solvent was removed, 35 20 ml of water, the solvent was removed, and the product was resulting in 4.2 g of a dark oil. purified by silica gel chromatography using 60% ethyl acetate, 40% hexane, and 0.1% triethylamine resulting in 2.2 2-Methyl-N-(6-methylpyridin-2-yl)guinolin-8-amine g of a yellow oil. Hvw=2,2'-(1.2-Phenylene)bis(1-pentyl-1H-benzimidazole) To a flask were added 4.2 g of 2-methylduinolin-8-amine, 40 To a flask were added 1.5g of 2,2'-(1,2-phenylene)bis(1H 4.6 g of 6-methyl-2-bromopyridine, 3.3 g of sodium tert benzimidazole) and 30 ml of N,N-dimethylformamide, and butoxide, and 75 ml toluene. The mixture was purged thor the mixture was cooled to 5 C. To this mixture was added 0.48 oughly with nitrogen and 44 mg of 1,1'-bis(diphenylphos g of 60% sodium hydride in mineral oil in small portions, and phino) ferrocene and 18 mg of palladium acetate were added. after stirring at 5-10 C for 30 minutes, 2.4 g of 1-1-iodopen The reaction mixture was heated to 80 C for 16 hours, and 45 tane were added. The reaction mixture was warmed to 22 C then cooled to 22 C. After quenching with 100 ml of water, the for and stirred for 16 hours, then quenched with 50 ml water. product was extracted with 75 ml ethyl acetate. The product The product was extracted with 40 ml ethyl acetate and fol was extracted with 120 ml of 1M hydrochloric acid, and then lowing removal of the solvent, the product was purified by basified with 3M sodium hydroxide. Following extraction silica gel chromatography using 25% ethyl acetate, 75% hex with 75 ml of ethyl acetate and washing with 30 ml of water, 50 ane and 0.1% triethylamine resulting in 2.1 g of a yellow the solvent was removed. The product was purified by dis solid. solving in a hot mixture of 20 ml of 2-propanol and 5 ml of Hwa 3-Methylpyridazine water, and after cooling to 5 C, the product was filtered, Hwc=1-Butyl-1H-imidazole washed with 50% 2-propanol, and dried, resulting in 4.5g of Hwd-Hexamethylphosphoramide a tan Solid. 55 What is claimed is: 1. A thermochromic device that comprises: 2-Methyl-N-(6-methylpyridin-2-yl)-N-pyridin-2- first and second thermochromic layers, wherein each ther ylquinolin-8-amine mochromic layer respectively contains a polymer, at least one transition metal ion, at least one HeL ligand To a flask were added 2.5g of 2-methyl-N-(6-methylpyri 60 capable of forming a HeMLC with the transition metal din-2-yl)guinolin-8-amine, 4.7 g of 2-bromopyridine, 1.6 g of ion, and at least one LeL ligand capable of forming a Sodium carbonate, 51 mg of copper bronze, 5 mg of potas LeMLC with the transition metal ion; sium bromide, and 3 ml of mesytylene. After stirring under wherein each layer exhibits a reversible net increase in nitrogen at 160 C for 16 hours, the mixture was cooled to 22 light energy absorbance in the visible and/or NIR range C, and 35 ml of water was added and the product was 65 as the temperature of the layer increases, and at elevated extracted with 50 ml ethyl acetate. After washing twice with temperatures, the light energy absorbance of the 20 ml of water, the solvent was removed, and the product was HeMLC in the first layer is greater than the light energy US 7,525,717 B2 133 134 absorbance of the HeMLC in the second layer for a 13. The device of claim 1 wherein at least one of the portion of the visible and/or NIR range. thermochromic layers contains two or more kinds of HeL's, 2. The device of claim 1 wherein at least one of the ther at least one of which is a halide, a pseudohalide, a phosphine, mochromic layers exhibits a net increase in light energy or a phosphinate. absorbance within the visible range. 14. The device of claim 1 wherein at least one of the 3. The device of claim 1 wherein at least one of the ther mochromic layers exhibits a net increase in absorbance thermochromic layers contains a diol, triol, or polyol LeL in within the NIR range. a layer of poly(vinylbutyral) wherein the layer contains less 4. The device of claim 1 wherein the device additionally than 1% water by weight. includes a separator between the first and second thermochro 10 15. The device of claim 1 wherein the transition metalions mic layers to prevent intermixing of the contents of the layers. include Ni(II) and/or Co(II). 5. The device of claim 4 wherein the separator has one or 16. The device of claim 1 wherein a NIR absorbance is more surfaces that are excited. provided by a complex of iodide and Co(II) ion and thermo 6. The device of claim 4 wherein the absorbance of the chromic activity is provided by an increase in the concentra device at 25°C. is less than about 0.3 throughout the visible 15 tion of a complex of iodide and Ni(II) ion. and NIR range and the absorbance of the device at 85°C. is greater than about 0.8 at some wavelength in the visible or 17. The device of claim 1 wherein each thermochromic NIR range. layer includes NiCII) and a halide. 7. The device of claim 1, wherein the transition metalion is 18. The device of claim 4 wherein the separator layer is present in an amount from about 0.02 moles to about 0.4 selected from poly(methyl methacrylate), poly(ester-tereph moles per kilogram of polymer. thalate), polycarbonate, poly(4-methyl-1-pentene), poly(vi 8. The device of claim 1 wherein the thermochromic layers nyl propionate), poly(vinyl acetate), poly(Vinyl methyl exhibit c of less than about 25 throughout the temperature ether), poly(ethylene Succinate), cellulose acetate butyrate, range of 25 to 85°C. with Y from greater than about 70% at cellulose acetate, ethylene/vinyl acetate copolymer, ethylcel 25° C. and less than about 15% at 85°C. 25 lulose, poly(methyl acrylate), poly(oxymethylene), poly(n- 9. The device of claim 1 wherein the thermochromic layers butyl methacrylate), poly(methyl methacrylate), polypropy exhibit c of less than about 20 throughout the range of 25 to lene, methylcellulose, poly(vinyl alcohol), poly(vinyl methyl 85°C. and a Y from greater than about 75% at 25° C. and less ketone), poly(ethylene glycol dimethacrylate), poly(isobuty than about 15% at 85°C. lene), and polyethylene. 10. The device of claim 1 wherein the device includes a 30 third thermochromic layer and the thermochromic layers 19. The device of claim 1 wherein the polymer is selected exhibit c of less than about 15 throughout the range of 25 to from poly(vinyl butyral); poly(hydroxyethyl methacrylate); 85°C. and a Y from greater than about 80% at 25° C. and less poly(1-glycerol methacrylate); hydroxyalkylcelluloses; ure than about 15% at 85°C. thanes; poly(2-ethyl-2-oxazoline); poly(N-vinylpyrroli 11. The device of claim 1 wherein the thermochromic 35 done); poly(ethylene-co-vinylalcohol); poly(vinyl methyl layers have a blue, green or bronze appearance at 25°C. and ether); poly(Vinylbutyral-co-vinylalcohol-co-vinylacetate); a c of less than 20 at 85 C. polyacrylamide: poly(N,N-dimethylacrylamide); polyvi 12. The device of claim 1 wherein the thermochromic nylpyridines and copolymers which involve the aforesaid layers exhibit an absorbance of about s().2 at 25°C. and an polymer functionalities. absorbance of about 20.8 at 85°C. at each wavelength in the 40 400 to 700 nm range.