USOO8524388B2

(12) United States Patent (10) Patent No.: US 8,524,388 B2 Dai et al. (45) Date of Patent: Sep. 3, 2013

(54) -DERIVED PROTIC IONIC Huang J-F et al., “A New Strategy for Synthesis of Novel Classes of LIQUIDS Room-Temperature Ionic Liquids Based on Complexation Reaction of Cations”, Journal of the Electrochemical Society 153(2):J9-J13 (2006). (75) Inventors: Sheng Dai, Knoxville, TN (US); Verkade J.G. et al., “Recent Applications of ProaZaphosphatranes in Huimin Luo, Knoxville, TN (US); Gary Organic Synthesis'. Aldrichimica Acta 37(1):3-15 (2004). A. Baker, Knoxville, TN (US) Belieres J-P et al., “Protic Ionic Liquids: Preparation, Characteriza tion, and Proton Free Energy Level Representation”. J. Phys. Chem. (73) Assignee. UT-Battelle, LLC, Oak Ridge, TN (US) B 1 11:4926-4937 (2007). Earle M.J. et al., “The Distillation and Volatility of Ionic Liquids'. (*) Notice: Subject to any disclaimer, the term of this Nature 439:831-834 (2006). patent is extended or adjusted under 35 Jin H. et al., “Physical Properties of Ionic Liquids Consisting of the U.S.C. 154(b) by 751 days. 1-Butyl-3-Methylimidazolium Cation With Various Anions and the Bis(Trifluoromethylsulfonyl)imide Anion With Various Cations”. J. (21) Appl. No.: 12/690,224 Phys. Chem. B. 112(1): 81-92 (2008). Ogihara W. et al., “Polarity Measurement for Ionic Liquids Contain (22) Filed: Jan. 20, 2010 ing Dissociable Protons', Chemistry Letters 33(11): 1414-1415 (2004). (65) Prior Publication Data Carmichael A.J. et al., “Polarity Study of Some 1-Alkyl-3- Methylimidazolium Ambient-Temperature Ionic Liquids With the US 2011 FO177428A1 Jul. 21, 2011 Solvatochromic Dye, Nile Red'. Journal of Physical Organic Chem istry 13:591-595 (2000). (51) Int. Cl. Luo H. et al., “Ultrastable Superbase-Derived Protic Ionic Liquids'. HOLM 6/00 (2006.01) The Journal of Physical Chemistry B Letters 113(13):4181-4183 HOLM 8/08 (2006.01) (2009). HOIG 9/02 (2006.01) (52) U.S. Cl. Primary Examiner — Johann R Richter USPC ...... 429/122; 429/498: 252/62.2 Assistant Examiner — Kofi Adzamli (58) Field of Classification Search (74) Attorney, Agent, or Firm — Scully, Scott, Murphy & USPC ...... 429/122,498: 252/62.2 Presser, P.C. See application file for complete search history. (57) ABSTRACT (56) References Cited Protic ionic liquids having a composition of formula (A) (BH) wherein A is a conjugate of an HA, and BH' PUBLICATIONS is a of a Superbase B. In particular embodi Greaves T.L. et al., “Protic Ionic Liquids: Properties and Applica ments, BH" is selected from phosphazenium species and tions”, Chem. Rev. 108(I):206-237 (2008). guanidinium species encompassed, respectively, by the gen Kolomeitsev A. A. et al., “GuanidionophosphaZenes: Design, Synthe eral formulas: sis, and Basicity in THF and in the Gas Phase'. J. Am. Chem. Soc. 127(50): 17656-17666 (2005). Fernicola A. et al., “New Types of Brönsted Acid-Base Ionic Liquids Based Membranes for Applications in PEMFCs”, ChemPhysChem 8: 1103-1107 (2007). Belieres J-Petal. "Binary Inorganic Salt Mixtures as High. Conduc tivity Liquid Electrolytes for >100° C. Fuel Cells”. Chem. Commun. pp. 4799-4801 (2006). Nakamoto H. et al., “Bronsted Acid-Base Ionic Liquids for Fuel Cell The invention is also directed to films and membranes con Electrolytes”, Chem. Commun. pp. 2539-2541 (2007). taining these protic ionic liquids, with particular application Susan A.B.H. et al., “Bronsted Acid-Base Ionic Liquids and Their as proton exchange membranes for fuel cells. Use as New Materials for Anydrous Proton Conductors', Chem. Commun. pp.938-939 (2003). 48 Claims, 9 Drawing Sheets U.S. Patent Sep. 3, 2013 Sheet 1 of 9 US 8,524,388 B2

No. " ' ". . . . faceous (i ... ------phase NO ------:- - - - - A r *%-"N ) Note: ---- s LiA (aq; ! ----. :- phasePL YN1- N 3.2,N N 8. CH H CH Chi, , A : TiN", bet

FIGURE 1 U.S. Patent Sep. 3, 2013 Sheet 2 of 9 US 8,524,388 B2

1000

99.8 1:(EtP(dma)HTfN) 2:(MTBDHTfN) 99.6 3:(EtP(dma)HTf,N) (bmim(Tf,N) SS 4:Et NHTf N) 99.4 CD st 99.2

99.0

98.8

98.6 O 100 200 300 400 500 600 700

FIG. 2 U.S. Patent Sep. 3, 2013 Sheet 3 of 9 US 8,524,388 B2

(MTBDHTfNG 150 °C 100.0 00071%h- 99.5

99.0

98.5

98.0 O 4 8 12 16 20 24 TIMEIh

FIG. 3 U.S. Patent Sep. 3, 2013 Sheet 4 of 9 US 8,524,388 B2

100 aus (MTBDHTfN) (ENH,EtNHNO INOs) (bmim(TfN) 60 EtNH)(Ti,N) s 40

20

O O 100 200 300 400 500 600 TEMPERATURE 1 °C

FIG. 4 U.S. Patent Sep. 3, 2013 Sheet 5 Of 9 US 8,524,388 B2

100

98

96

94

92

90 O 50 100 150 200 250

TIME 1 min

FIG. 5 U.S. Patent Sep. 3, 2013 Sheet 6 of 9 US 8,524,388 B2

(MTBDH (Tf.N.

- G.O

... I 1.0

. . . . -o-a-do--- 85 9 5 CO 2.0S 2 ( 2.5 10 K T

FIGURE 6 U.S. Patent Sep. 3, 2013 Sheet 7 of 9 US 8,524,388 B2

3 o (t-BuP (dma)H)(beti s 2 s O - H 1 CC L C O 30 °C 2.5:1.0 (t-BuP (dma)H)(bett)/ (bmim(Tf,N) -1 -100 -50 O 50 100 150

TEMPERATURE / C

FIG. 7 U.S. Patent Sep. 3, 2013 Sheet 8 of 9 US 8,524,388 B2

U.S. Patent Sep. 3, 2013 Sheet 9 Of 9 US 8,524,388 B2

US 8,524,388 B2 1. 2 SUPERBASE-DERVED PROTCONC BRIEF DESCRIPTION OF THE DRAWINGS LIQUIDS FIG.1. Scheme showing a general method for preparation This invention was made with government Support under of the protic ionic liquids of the invention. Contract Number DE-AC05-00OR22725 between the United 5 FIG. 2. Isothermal TGA scans conducted under nitrogen States Department of Energy and UT-Battelle, LLC. The U.S. (N) atmosphere at 150° C. showing the superior thermal government has certain rights in this invention. stability of EtB, (dma)HITFN and MTBDHITf.N as compared to the conventional PIL EtNHTf.N. FIELD OF THE INVENTION FIG.3. Isothermal TGA scan for MTBDHTf.N. at 150° 10 C. under flowing nitrogen (60 mL/min). The short dashed The present invention relates generally to the field of ionic profile shows the linear regression line resulting from these liquids, and more particularly, to protic ionic liquids. data. FIG. 4. TGA profile for the superbase-derived PIL (MT BACKGROUND OF THE INVENTION BDHIITf.N compared to those of two conventional PILs 15 (EtnHINO and Et-NHTfNI), and that for the proto Protic ionic liquids (PILs) are being intensively studied as type aprotic ionic liquid (AIL) BMIMITf.N. Measure advanced materials for numerous specialized applications. ments were performed under nitrogen using a scan rate of 10° Some of these applications include their use as protontransfer C./min. electrolytes and membranes in proton-exchange membrane FIG. 5. Time-dependent isothermogravimetry curves of fuel cells (PEMFCs), as well as their use as separation mate MTBDHTf, showing the linear mass losses at five dis rials and solvent systems in chemical reactions. crete temperatures. A significant problem encountered with protic ionic liquids FIG. 6. Graph showing temperature dependence of the has been their propensity to degrade over time, and particu mass loss of MTBDHTf.N. based on the results summa larly, under elevated temperature conditions (e.g., tempera rized in FIG. 5. The plot yields a gradient of AH/R, where tures greater than 100° C., as generally encountered in PEM 25 AH is the vaporization enthalpy, R is the gas constant, T is FCs). The degradation is generally a result of retro-proton the Kelvin temperature, and k equals the observed rate of transfer between the constituentions (i.e., conjugate base A mass loss normalized to vessel cross section. and conjugate acid BH) of the protic ionic liquid, depicted as FIG. 7. DSC thermogram (warming cycle, 20°C/min) of follows: neat t-BuP (dma)HIBETI (upper curve) illustrating the 30 measurement of the melting temperature, Tfus, and the for mation of a eutectic melting near ambient via addition of 28.5 The resulting acid (HA) and base (B) lack strong Coulom vol% of the AIL BMIMITfN (lower curve). bic interactions, and thus, their generation results in a marked FIGS. 8A, 8B, 8C, Et NHTfN (left vial) and MT vaporization (i.e., volatility), and hence, increase in vapor BDHITf,N (right vial) dyed with Nile Redbefore (FIG.8A) pressure, of the ionic liquid. The degradation also leads, nec 35 and after (FIG. 8B) addition of concentrated KOH (aq). FIG. essarily, to electrolyte loss. Particularly in the case of fuel 8C shows Nile Red in various water-to-ethanol volume ratio cells, the electrolyte loss at higher temperatures is detrimental Solutions. for several reasons, particularly in causing a reduced fuel cell FIG. 9. EtNHITf.N (left vial) and MTBDHIIT?,N) operational lifetime and performance. (right vial) in the presence of 1.0 Naqueous KOH containing Accordingly, there is a need for new protic ionic liquid 40 the indicator Thymol Blue (TB). compositions that possess an improved stability, particularly at elevated temperatures. There is a particular need for such DETAILED DESCRIPTION OF THE INVENTION protic ionic liquids that also can be used as conductive com ponents of proton exchange membranes. The terms “hydrocarbon group' and “hydrocarbon linker, 45 as used herein, are, in a first embodiment, composed solely of SUMMARY OF THE INVENTION carbon and hydrogen. In different embodiments, one or more of the hydrocarbon groups or linkers can contain precisely, or In one aspect, the invention is directed to a protic ionic a minimum of, or a maximum of for example, one, two, three, liquid (PIL) having a composition of formula (A)(BH') four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, wherein A is a conjugate base of an acid HA, and BH" is a 50 fourteen, fifteen, sixteen, seventeen, or eighteen carbon conjugate acid of a Superbase B. In a particular embodiment, atoms, or a particular range of carbon atoms between any of BH" is a phosphaZeno-containing Superbase. In another par the foregoing carbon numbers. Hydrocarbon groups of dif ticular embodiment, BH is a guanidino-containing Super ferent ionic liquid compounds described herein may possess base. In other embodiments, BH" is a guanidinophosp the same or different number (or preferred range thereof) of haZene-containing Superbase. In other particular 55 carbonatoms in order to independently adjust or optimize one embodiments, A is a conjugate base of a HA. or more characteristics of each type of ionic liquid. In another aspect, the invention is directed to a film (e.g., a The hydrocarbon groups or linkers can be, for example, membrane) that contains the ionic liquid described above. saturated and straight-chained (i.e., straight-chained alkyl The film is particularly contemplated herein to be useful as a groups or alkylene linkers). Some examples of straight proton exchange membrane of a fuel cell. 60 chained alkyl groups (or alkylene linkers) include methyl (or The PIL compositions described herein are advanta methylene, i.e., —CH2—, or methine linkers), ethyl (or eth geously resistant to degradation by retro-proton transfer, par ylene or dimethylene, i.e., —CH2CH2— linkers), n-propyl. ticularly at elevated temperatures. Accordingly, the PIL com n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-de positions described herein are more Suited than conventional cyl. n-undecyl. n-dodecyl, n-tridecyl, n-tetradecyl. n-penta ionic liquids of the art for use in high temperature applica 65 decyl, n-hexadecyl, n-heptadecyl, and n-octadecyl groups. tions, such as in proton exchange membranes of PEM-type The hydrocarbon groups or linkers can alternatively be fuel cells. saturated and branched (i.e., branched alkyl groups or alky US 8,524,388 B2 3 4 lene linkers). Some examples of branched alkyl groups Some examples of oxygen-containing groups include include isopropyl, isobutyl, sec-butyl, t-butyl, isopentyl, neo hydroxyl (OH) groups, carbonyl groups (e.g., ketone, alde pentyl, 2-methylpentyl, 3-methylpentyl, and the numerous hyde, ester, amide, or urea functionalities), and carbon-oxy C7, Cs. Co. Co. C 1, C12, C1s, C14, C1s, C6, C17, and C1s gen-carbon (ether) groups. The ether group can also be a saturated and branched hydrocarbon groups. Some examples 5 polyalkyleneoxide group, Such as a polyethyleneoxide group. of branched alkylene linkers are those derived by removal of Some examples of nitrogen-containing groups include pri a hydrogen atom from one of the foregoing exemplary mary amine groups, secondary amine groups, tertiary amine branched alkyl groups (e.g., isopropylene, —CH(CH) groups, quaternary amine groups, cyanide group, amide CH, ). group (i.e., —C(O)NR, wherein R is independently selected The hydrocarbon groups or linkers can alternatively be 10 from hydrogen atom and hydrocarbon group, as described saturated and cyclic (i.e., cycloalkyl groups or cycloalkylene above), nitro group, urea group, imino group, and carbamate linkers). Some examples of cycloalkyl groups include cyclo group, wherein it is understood that a quaternary amine group propyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and necessarily possesses a positive charge and requires a coun cyclooctyl groups. The cycloalkyl group can also be a poly teranion. Some examples of sulfur-containing groups include cyclic (e.g., bicyclic) group by either possessing a bond 15 mercapto (i.e., —SH), thioether (i.e., sulfide), disulfide, sul between two ring groups (e.g., dicyclohexyl) or a shared (i.e., foxide, Sulfone, Sulfonate, and Sulfate groups. Halide atoms fused) side (e.g., decalin and norbornane). Some examples of considered herein include fluorine, chlorine, and bromine. cycloalkylene linkers are those derived by removal of a Some examples of fluorine-containing hydrocarbon groups hydrogen atom from one of the foregoing exemplary (i.e., fluorocarbon groups) include the partially-substituted cycloalkyl groups. varieties (e.g., fluoromethyl, difluoromethyl 2-fluoroethyl, The hydrocarbon groups or linkers can alternatively be 2,2-difluoroethyl, 2.2.2-trifluoroethyl, fluorobenzene, fluo unsaturated and straight-chained (i.e., Straight-chained ole robenzyl, and the like) and perfluoro-substituted varieties finic or alkenyl groups or linkers). The unsaturation occurs by (e.g., perfluoromethyl, perfluoroethyl, perfluoropropyl, per the presence of one or more carbon-carbon double bonds fluorobutyl, pentafluorophenyl, and the like). Some examples and/or one or more carbon-carbon triple bonds. Some 25 of phosphorus-containing groups include dialkylphosphine, examples of Straight-chained olefinic groups include vinyl, dialkenylphosphine, arylphosphine, diarylphosphine, phos 2-propen-1-yl (allyl), 3-buten-1-yl, 2-buten-1-yl, butadienyl, phinidene, phosphaZene, phosphine oxide, phosphinite, 4-penten-1-yl, 3-penten-1-yl, 2-penten-1-yl, 2.4-pentadien phosphinate, phosphonite, phosphonate, phosphite, phos 1-yl, 5-hexen-1-yl 4-hexen-1-yl, 3-hexen-1-yl, 3.5-hexa phate, and phosphonium groups. dien-1-yl, 1.3.5-hexatrien-1-yl, 6-hepten-1-yl, ethynyl, prop 30 Of the heteroatom groups described above, particular con argyl (2-propynyl), and the numerous C7, Cs, Co. Co., C. sideration is given to amino groups, such as described by the C2, C1s, C14, C1s, C6, C7, and C1s unsaturated and straight following formula: chained hydrocarbon groups. Some examples of straight chained olefinic linkers are those derived by removal of a NRI2R13 (1) hydrogenatom from one of the foregoing exemplary straight 35 In formula (4) above, R'' and R' are each independently chained olefinic groups (e.g., vinylene, —CH=CH-, or selected from a hydrogen atom and any of the hydrocarbon vinylidene). groups described above, including unsubstituted and heteroa The hydrocarbon groups or linkers can alternatively be tom-substituted hydrocarbon groups. The hydrocarbon unsaturated and branched (i.e., branched olefinic or alkenyl groups particularly considered herein for R'' and R' contain groups or linkers). Some examples of branched olefinic 40 at least one, two, or three carbon atoms and up to four, five, groups include 2-propen-2-yl, 3-buten-2-yl, 3-buten-3-yl, six, seven, or eight carbon atoms. 4-penten-2-yl 4-penten-3-yl 3-penten-2-yl, 3-penten-3-yl, The groups R'' and R' informula (1) can, in one embodi 2.4-pentadien-3-yl, and the numerous C, C7, Cs, Co, Co. ment, be non-interconnected. Some examples of amino C1, C12, C1s, C14, C1s, C6, C7, and C1s unsaturated and groups according to formula (1) in which R'' and R' are branched hydrocarbon groups. Some examples of branched 45 non-interconnected include amino ( NH), methylamino olefinic linkers are those derived by removal of a hydrogen ( N(H)CH), dimethylamino (dma), ethylamino, diethy atom from one of the foregoing exemplary branched olefinic lamino, n-propylamino, di(n-propyl)amino, isopropylamino, groups. diisopropylamino, n-butylamino, di(n-butyl)amino, isobuty The hydrocarbon groups or linkers can alternatively be lamino, diisobutylamino, sec-butylamino, di(sec-butyl) unsaturated and cyclic (i.e., cycloalkenyl groups or cycloalk 50 amino, t-butylamino, di(t-butyl)amino, n-pentylamino, di(n- enylene linkers). Some examples of unsaturated and cyclic pentyl)amino, isopentylamino, diisopentylamino, hydrocarbon groups include cyclopropenyl, cyclobutenyl, neopentylamino, n-hexylamino, di(n-hexyl)amino, isohexy cyclopentenyl, cyclopentadienyl, cyclohexenyl, cyclohexadi lamino, n-heptylamino, n-octylamino, di(n-octyl)amino, enyl, phenyl, benzyl, cycloheptenyl, cycloheptadienyl, isooctylamino, vinylamino, allylamino, diallylamino, cyclooctenyl, cyclooctadienyl, and cyclooctatetraenyl 55 cyclobutylamino, cyclopentylamino, cyclohexylamino, phe groups. The unsaturated cyclic hydrocarbon group can also nylamino, diphenylamino, benzylamino, dibenzylamino, be a polycyclic (e.g., bicyclic) group by either possessing a hydroxymethylamino (HOCH-NH ), di(hydroxymethyl) bond between two of the ring groups (e.g., biphenyl) or a amino, methoxymethylamino, hydroxyethylamino, di(hy shared (i.e., fused) side (e.g., naphthalene, anthracene, droxyethyl)amino, methoxyethylamino, ethoxyethylamino, phenanthrene, phenalene, and indene). Some examples of 60 2-(hydroxy)ethoxy-methylamino cycloalkenylene linkers are those derived by removal of a (HOCHCHOCH-NH ), 2-2-(hydroxy)ethoxyethy hydrogen atom from one of the foregoing exemplary lamino (HOCH2CHOCH2CH-NH ), aminomethylamino cycloalkenyl groups (e.g., phenylene and biphenylene). (HNCH-NH ), and 2-aminoethylamino One or more of the hydrocarbon groups or linkers may also (HNCHCH-NH ) groups. include one or more heteroatoms (i.e., non-carbon and non 65 In another embodiment, the groups RandR' informula hydrogen atoms). Such as one or more heteroatoms selected (1) are interconnected, thereby making the amino group of from oxygen, nitrogen, Sulfur, halide, and phosphorus atoms. formula (1) an amino-containing ring group. Some examples US 8,524,388 B2 5 6 of amino groups according to formula (1) in which R', and embodiment, two of R', R' and Rare selected from any of R" are interconnected include azacyclopropyl (aziridinyl or the amino and/or imino groups described above, while one of dimethyleneiminyl), azacyclobutyl (azetidinyl or trimethyl R". R' and R' is a hydrocarbon group. In a fourth embodi eneiminyl), pyrrolidinyl, pyrrolyl, imidazolyl, imidazolidi ment, all of R', R'' and R' are selected from any of the nyl, oxazolyl pyrazolyl, piperidinyl, piperazinyl, morpholi amino and/or imino groups described above. In one embodi nyl, pyridinyl, pyrimidinyl, pyrazinyl, triazinyl, ment, R', R' and R are non-interconnected. In other triazacyclohexyl, azacycloheptyl (homopiperidinyl), azacy embodiments, two or three of R', R'' and Rare intercon looctyl, indolyl, benzimidazolyl, purinyl, quinolinyl, decahy nected. droquinolinyl, and bipyridyl groups. 10 In formula (1b), one, two, or all of R', R'' and R' can, The groups R'' and R' in formula (1) can also together themselves, also be phosphaZeno groups as depicted in for represent a double bond connecting the shown nitrogenatom mula (1b). The foregoing three embodiments are encom to a carbon atom, with the result of forming an imino group, passed by the following three subformulas of formula (1b): as represented by the following formula: 15 1c (1a) NPR43R44 R45 (1c) -NE f -R R42 1d N-PR43R44 R45 ( ) Informula (1a), R'' and R' can independently be selected from a hydrogenatom, any of the Substituted or unsubstituted -N f -N PR46R47R48 hydrocarbon groups described above bound to the shown C 25 R42 atom by a carbon atom, or an amino group (as depicted by 1e formula (1)) bound to the shown C atom by its nitrogenatom. E PR43R44R45 ( ) R'' and R' can also be either non-interconnected or inter connected. In a first embodiment, both R'' and Rare hydro -NE NEPR6R47R8 gen atoms. In a second embodiment, R'' is a hydrogen atom N and R' is a hydrocarbon group. In a third embodiment, R'' is 30 a hydrogen atom and R' is an amino group. In a fourth embodiment, both of R'' and R' are hydrocarbon groups. In In formulas (1c), (1 d), and (1e), R. R. R. R. R7, a fifth embodiment, R'' is a hydrocarbon group and R' is an R. R. R', and R are independently selected from amino group. In a sixth embodiment, both of R'' and Rare unsubstituted or heteroatom-Substituted hydrocarbon groups, amino groups. When R'' and R'' are both amino groups, 35 and/or amino groups according to formula (1), and/or imino formula (1a) represents a guanidino group. The guanidino groups according to formula (1a), and/or phosphaZeno group is an acyclic guanidino group when R'' and R' are groups according to formula (1b). non-interconnected. The guanidino group is a cyclic guani dino group when R'' and R' are interconnected. Some par In one aspect, the invention is directed to novel protic ionic ticular examples of cyclic guanidine groups include imidazo 40 liquid (PIL) compositions. The PIL compositions can be con lidin-2-ylideneamino, 1,3-dihydro-2H-imidazol-2- veniently described by the formula (A)(BH'), wherein A is ylideneamino, and (1,3-dimethylimidazolidin-2-ylidene) a conjugate base of an acid HA, and BH" is a conjugate acid amino. of a Superbase B. The foregoing formula is meant to encom The groups R'' and R' in formula (1) can also together pass a conjugate base having any Valency of negative charge represent a double bond connecting the shown nitrogenatom 45 and a conjugate acid having any Valency of positive charge, to a phosphorus atom, with the result of forming a phosp provided that the charge contributions from the conjugate haZeno group, as represented by the following formula: base and conjugate acid are counterbalanced in order for charge neutrality to be preserved in the ionic liquid molecule. 50 More specifically, the formula (A)(BH") is meant to encom (1b) pass the more generic formula (A*),(BH'), wherein the variables a and b are, independently, non-zero integers, and the variables X and y are, independently, non-Zero integers, such that a.x=by (wherein the period placed between vari ables indicates multiplication of the variables). The foregoing 55 generic formula encompasses numerous possible Sub-formu In formula (1b), R', R'' and R' can independently be las, such as, for example, (A)(BH"), (A)(BH"), (A), selected from amino groups, as shown in formula (1), bound (BH'), (A)(BH) (A)(BH) (A)(BH'), (A), to the shown Patom by a nitrogenatom; and imino groups, as (BH'), and (A)(BH"). shown in formula (1a), bound to the shown Patom by a 60 The Superbase B can be any Superbase. Generally, a Super nitrogen atom; and any of the Substituted or unsubstituted base is distinguished from an ordinary base by having an acid hydrocarbon groups described above bound to the shown P , i.e., pKa, of its conjugate acid BH', of atom by a carbonatom. In a first embodiment, all of R', R' 20 or above in acetonitrile (or 12 or above in water). In other and R are selected from any of the hydrocarbon groups embodiments, the Superbase is characterized by having a pKa described above. In a second embodiment, two of R". R' 65 of its conjugate acid BH" of at least 21, 22, 23, 24, 25, 26, 27. and Rare selected from hydrocarbon groups while one of 28, 29, or 30 in acetonitrile, or at least 13, 14, 15, or 16 in R", R'' and R is an amino group orimino group. In a third Water. US 8,524,388 B2 7 8 In one embodiment, BH has a phosphaZene composition result when R', R, and Rare independently selected from within the following generic formula: unsubstituted or heteroatom-Substituted hydrocarbon groups, and particularly, hydrocarbon groups containing at least one, two, or three carbon atoms and up to four, five, six, seven, or (2) eight carbon atoms (e.g., methyl, ethyl, n-propyl, isopropyl. R3 n-butyl, isobutyl, Sec-butyl, t-butyl, n-pentyl, isopentyl, neo pentyl, n-hexyl, n-heptyl, n-octyl, isooctyl, phenyl, benzyl, and tolyl groups), and/or amino groups according to formula (1), and/or imino groups according to formula (1a), and/or 10 phosphaZeno groups according to formulas (1 b), (1c), (1 d), In formula (2) above, R', R, and R are each indepen and/or (1e), and R is a hydrogenatom or any of the foregoing dently selected from any of the unsubstituted or heteroatom exemplary hydrocarbon groups. In a first set of embodiments, substituted hydrocarbon groups described above and bound all three of R', R, and Rare independently selected from to the shown Patom by a carbon atom; and/or amino groups hydrocarbon groups, and particularly, any of the foregoing of formula (1) bound to the Patom shown in formula (2) by 15 exemplary hydrocarbon groups. In a second set of embodi the nitrogenatom shown informula (1); and/or imino groups ments, two of R', R, and Rare independently selected from of formula (1a) bound to the Patom shown in formula (2) by hydrocarbon groups, and one of R', R, and R is selected the nitrogen shown in formula (1a); and/or phosphaZeno from any of the amino groups according to formula (1), and/ or imino groups according to formula (1a), and/or phosp groups of formulas (1b), (1c), (1d), and/or (1e) bound to the P haZeno groups according to formulas (1b), (1c), (1 d), and/or atom shown informula (2) by the nitrogen shown informulas (1e). In a third set of embodiments, one of R', R, and R is (1b), (1c), (1 d), and/or (1e). The group R is either a hydrogen selected from hydrocarbon groups, and two of R', R, and R' atom or any of the unsubstituted or heteroatom-substituted are independently selected from any of the amino groups hydrocarbon groups described above. When R is a heteroa according to formula (1), and/or imino groups according to tom-substituted hydrocarbon group, R' can be bound to the formula (1a), and/or phosphaZeno groups according to for shown nitrogenatom by a carbon atom, or a heteroatom, Such 25 as a phosphorus atom (thereby forming an additional phosp mulas (1b), (1c), (1d), and/or (1e). In a fourth set of embodi haZene bond) or nitrogen atom (thereby forming a diazene ments, all three of R', R, and Rare independently selected bond). The subscript t is 0 or 1, to indicate, respectively, the from any of the amino groups according to formula (1), and/ absence or presence of the group R N=. A provision is or imino groups according to formula (1a), and/or phosp made that, whentis 0, at least one (i.e., one, two, orall) of R', haZeno groups according to formulas (1b), (1c), (1 d), and/or R, and R is selected from amino groups according to for 30 (1e). mula (1) and/or imino groups according to formula (1a) and/ In another particular embodiment of formula (2), t is 0, and orphosphaZeno groups according to formulas (1b), (1c), (1 d), thus, formula (2) encompasses phosphaZene species of the and/or (1e). The hydrogen ion depicted in formula (2) by the following chemical formula: symbol.H" is typically attached to one or more nitrogen or phosphorus atoms of the chemical structure. 35 In one embodiment, R. R. R. and R' of formula (2) are (2b) not interconnected. In another embodiment, two of R', R, R, and R of formula (2) are interconnected by one or more covalent chemical bonds (e.g., carbon-carbon, carbon-oxy gen, and/or carbon-nitrogen bonds). When two of R', R, and 40 Rare interconnected, a phosphorus-containing ring results, which includes the phosphorus atom shown informula (2). In The groups R', R, and R of formula (2b) retain their another embodiment, all of R', R, and Rof formula (2) are meanings as described above for formulas (2) and (2a), with interconnected by covalent chemical bonds. When all of R', the provision that at least one (i.e., one, two, orall) of R', R, R, and Rare interconnected, a phosphorus-containing bicy 45 and R is selected from amino groups according to formula clic ring system results, which includes the phosphorus atom (1), and/or imino groups according to formula (1a), and/or shown informula (2). When one or more of R', R, and Rare phosphaZeno groups according to formulas (1b), (1c), (1 d), selected from amino groups, and/or imino groups, and/or and/or (1e). The second, third, and fourth exemplary sets of phosphaZeno groups (i.e., according to, respectively, formu embodiments for R. R. and R described above under for las (1), (1a), or (1b)), an interconnection of two or three of R', mula (2a) are also incorporated herein. R, and R results, respectively, in a phosphazene-containing 50 In another particular embodiment of formula (2), R. R. ring or bicyclic ring system, which includes the phosphorus and Rare amino groups according to formula (1), and thus, atom shown informula (2) and one or more nitrogenatoms of formula (2) encompasses phosphaZene species within the the one or more amino, imino, and/or phosphaZeno groups. following chemical formula: In a particular embodiment of formula (2), t is 1, and thus, formula (2) encompasses phosphaZene species of the follow 55 ing chemical formula: (3) NRSR6 M (R-NEP-NRN H" (2a) 60 NR9R 10 In formula (3), R. R. R. R. R. R', and R'' are each independently selected from a hydrogen atom and any of the substituted or unsubstituted hydrocarbon groups described The groups R', R. R. and R' of formula (2a) retain their 65 above. Optionally, two, three, or more of R. R. R. R. R. meanings as described above for formula (2). Particularly and R'' are interconnected. The subscript t is 0 or 1, as contemplated herein for formula (2a) are the species that described above. In particular embodiments, at least one, two, US 8,524,388 B2 9 10 three, four, five, or all of R. R. R. R. R. and R'' are amino groups according to formula (1), and/or imino groups independently selected from hydrocarbon groups, and par according to formula (1a), and/or phosphaZeno groups ticularly, those hydrocarbon groups containing at least one, according to formulas (1b), (1c), (1 d), and/or (1e), all as two, or three carbon atoms and up to four, five, six, seven, or described above. The subscript t is 0 or 1, as described above. eight carbon atoms (e.g., methyl, ethyl, n-propyl, isopropyl. In particular embodiments of formula (4), at least one, two, n-butyl, isobutyl, Sec-butyl, t-butyl, n-pentyl, isopentyl, neo three, four, five, or all of R', R'7, R. R. R', and R are pentyl, n-hexyl, n-heptyl, n-octyl, isooctyl, phenyl, benzyl, independently selected from hydrocarbon groups, and par ticularly, hydrocarbon groups containing at least one, two, or and tolyl groups), and if R''N= is present, R'' is a hydrogen three carbon atoms and up to four, five, six, seven, or eight atom or any of the foregoing exemplary hydrocarbon groups. carbon atoms (e.g., methyl, ethyl, n-propyl, isopropyl. n-bu In a particular embodiment of formula (3), t is 1, and thus, 10 tyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, neopen formula (3) encompasses phosphaZene species of the follow tyl, n-hexyl, n-heptyl, n-octyl, isooctyl, phenyl, benzyl, and ing chemical formula: tolyl groups), and if R''N= is present, R'' is a hydrogen atom or any of the foregoing exemplary hydrocarbon groups. (3a) In other embodiments of formula (4), at least one of R". R'7, NRSR6 15 R. R. R', and R' (i.e., one, two, three, four, five, or all of R. R'7, R. R. R. and R') is selected from amino groups according to formula (1), and/or imino groups accord ing to formula (1a), and/or phosphaZeno groups according to Informula (3a), R. R. R. R. R. R', and R' retain their formulas (1b), (1c), (1 d), and/or (1e). meanings as given under formula (3). All exemplary embodi Optionally, two or more of R'', R', R'7, R. R. R., and ments given above for these groups are also incorporated R’ are interconnected. When only R'' and R'', or R' and herein. In a particular embodiment, two of R. R. R. R. R. R", or R'' and R', or a combination thereof, are intercon and R' are interconnected to form a cyclic phosphazene nected, a cyclic imino group results, but the imino groups are structure, Such as the following structure: not interconnected to each other (and thus, the resulting ring 25 does not include the shown phosphorus atom). When groups (3.b) belonging to different imino groups interconnect with each NR'R' R8 other (e.g., R'' and R''), then a cyclic phosphazene species / results which contains one or more rings that include the shown phosphorus atom. In other embodiments, R'', R', A 30 R7, R. R. R', and R are not interconnected. R10 In a particular embodiment of formula (4), t is 1, and thus, formula (4) encompasses phosphazene species of the follow Informula (3b), R. R. R. R', and R' retain their mean ing chemical formula: ings as given under formula (3). All exemplary embodiments given above for these groups are also incorporated herein. In 35 particular embodiments of formula (3b), R. R. R. R', and (4a) R'' are independently selected from hydrocarbon groups R 16 containing 1 to 4 carbon atoms, and particularly, straight chained or branched alkyl groups containing 1 to 4 carbon 1. atoms. The curved line in formula (3.b) represents a hydro N R17 R18 carbon linker, such as any of the linkers described above, and 40 N particularly, an ethylene or trimethylene linker. In other particularembodiments of formula (3), at least one N R20 R19 of the shown amino groups (i.e., one, two, or all of NRR, N -NR'R', and NR'R'') is independently selected from R21 imino groups of formula (1a) and/or phosphaZeno groups of 45 formulas (1b), (1c), (1 d), and/or (1e). Informula (4a) above, R'', R', R'7, R,R,R, and R' In the particular case when all of the shown amino groups retain their meanings as given under formula (4). All exem of formula (3) are imino groups of formula (1), formula (3) plary embodiments given above for these groups are also encompasses phosphaZene species of the following chemical incorporated herein. formula: 50 In the particular case when all of the shown amino groups of formula (3) are phosphaZeno groups of formulas (1b). (1c), (1 d), and/or (1e), formula (3) encompasses phosphaZene spe (4) R 16 cies of the following chemical formula:

55 N R17 / R18 (R-N=-N={\ R19 oH' 20 60 N In formula (5), R0, R, R2, Rio, R, R2, Rio", Ri", R21 and R'' are as defined under formula (1b), i.e., indepen dently selected from unsubstituted or heteroatom-substituted Informula (4) above, R'', R', R'7, R. R. R', and R' 65 hydrocarbon groups, and/or amino groups according to for are each independently selected from a hydrogen atom, and/ mula (1), and/or imino groups according to formula (1a). or Substituted or unsubstituted hydrocarbon groups, and/or and/or phosphaZeno groups according to formulas (1b), (1c), US 8,524,388 B2 11 12 (1d), and/or (1e). The group R is selected from a hydrogen Optionally, two or more of R. R. R. R. R. and R' of atom or unsubstituted or heteroatom-substituted hydrocarbon formula (6) are interconnected. In one embodiment, Rand group, as described above, including particular exemplary R, or RandR, or Rand R', are interconnected to form a embodiments. In a first set of embodiments, at least one (i.e., nitrogen-containing ring. In another embodiment, one or both one, two, three, four, five, six, seven, eight, orall) of R', R', 5 of Rand Rare interconnected with one or two of R. R. R. R. R. R. R. R." R'", and R'" is selected from and R''. For example, Rican be connected with R" to form hydrocarbon groups. In a second set of embodiments, at least the following structure: one (i.e., one, two, three, four, five, six, seven, eight, or all) of R0, R, R2, R0, R, R2, RO", R", and R2" is selected from amino groups according to formula (1). In a third set of 10 (6a) embodiments, at least one (i.e., one two, three, four, five, six, seven, eight, or all) of R, R, R, RO, R, R2, R", R", and R'" is selected from imino groups according to formula (1a). In a fourth set of embodiments, at least one (i.e., one, two, three, four, five, six, seven, eight, orall) of R', R', 15 R. R. R. R. R." R'", and R'" is selected from phosphaZeno groups according to formulas (1b), (1c), (1 d), and/or (31e). In a fifth set of embodiments of formula (5), R' is a hydrocarbon group, and particularly, a hydrocarbon In formula (6a), the curve represents an interconnection group containing at least one, two, or three carbon atoms and 20 between RandR'. The interconnection can be, for example, up to four, five, six, seven, or eight carbonatoms (e.g., methyl, ethyl, n-propyl, isopropyl. n-butyl, isobutyl, sec-butyl, t-bu any of the unsubstituted or substituted hydrocarbon linkers tyl, n-pentyl, isopentyl, neopentyl, n-hexyl, n-heptyl, n-octyl, described above. In particular embodiments, the interconnec isooctyl, phenyl, benzyl, and tolyl groups). In addition, any tion is a dimethylene, trimethylene, or tetramethylene linker, two or more of R0, R, R2, R0, R, R2, Ro", R", R2", 25 optionally Substituted by one, two or more nitrogen or oxygen and R7 may be interconnected. For example, two or three of atoms. R can additionally be linked to R', or alternatively, to R', R', and R', and/or two or three of R, R, and R', R. to form, respectively, the following structures (wherein and/or two or three of R. R', and R', may be intercon each curve can be independently selected from linker groups nected. described above): In a particular embodiment of formula (5), t is 1, and thus, 30 formula (5) encompasses phosphaZene species of the follow ing chemical formula: (6b)

(6c)

In formula (5a) above, R, R', R,R,R,R, R", R'", R', and R' retain their meanings as given under formula (5). All exemplary embodiments given above for these groups are also incorporated herein. In a particular embodiment of formula (6), R. R. and R' In another particular embodiment of formula (3), t is 0, and 45 are interconnected according to the following formula: thus, formula (3) encompasses phosphaZene species of the following chemical formula: (6d)

56 (6) 50 NRR P-NR7RS H NR9R 10 55 In formula (6), R. R. R. R. R. and R'' are as defined under formula (3), i.e., independently selected from a hydro Informula (6d), the curves represent linkers that connect to gen atom and any of the Substituted or unsubstituted hydro each other by a covalent bond (i.e., at a connection point). The carbon groups described above. In particular embodiments, at connection point can include any suitable linking atom (e.g., least one, two, three, four, five, orall of R,R,R,R,R, and 60 carbon atom, oxygen atom, or nitrogen atom), or a heteroa R'' are independently selected from hydrocarbon groups, and tom linking group (e.g., amide, carbonyl, urea, ethylene gly particularly, hydrocarbon groups containing at least one, two, colate), or a linking ring group (e.g., 1.3.5-phenylene or 1.3, or three carbonatoms and up to four, five, six, seven, or eight 5-cyclohexylene). In a first set of embodiments of formula carbon atoms (e.g., methyl, ethyl, n-propyl, isopropyl. n-bu (6d), R. R. and Rare not interconnected. In another set of tyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, neopen- 65 embodiments of formula (6d), one, two, or all of R. R', and tyl, n-hexyl, n-heptyl, n-octyl, isooctyl, phenyl, benzyl, and R are interconnected to a portion of one or more of the tolyl groups). linkers. US 8,524,388 B2 13 14 In a further embodiment of formula (6d), the linkers are - NR7R, and NR'R'') is independently selected from attached to each other via an intermediate nitrogenatom (i.e., imino groups of formula (1a) and/or phosphaZeno groups of a nitrogen atom functions as a connection point), as depicted formulas (1b), (1c), (1 d), and/or (1e). in the following chemical formula: In the particular case when all of the shown amino groups of formula (6) are imino groups of formula (3), formula (6) encompasses phosphaZene species of the following chemical (6e) formula:

10 (7)

15 Formula (6e) encompasses the compounds known as aza phosphatranes. The synthesis of several of these types of compounds is detailed in J. G. Verkade and P. B. Kisanga, Aldrichimica Acta, vol. 37, no. 1 (2004), the disclosure of R21 which is incorporated herein by reference in its entirety. In the aZaphosphatranes, the hydrogen ion is typically attached to the phosphorus atom. In formula (7) above, R', R'7, R. R. R', and R are In a particular embodiment of formula (6e), each of the as defined in formula (4), i.e., each independently selected linkers is an ethylene linker. The resulting structure can be from a hydrogen atom, and/or Substituted or unsubstituted conveniently depicted by the following chemical formula: 25 hydrocarbon groups, and/or amino groups according to for mula (1), and/or imino groups according to formula (1a). and/or phosphaZeno groups according to formulas (1b), (1c), (1d), and/or (1e), all as described above. Optionally, two or R5 (6f) more of R. R. R. R. R', and R'' are interconnected, 30 as described under formula (4). In particular embodiments of R9 N-I 4. R o formula (7), at least one, two, three, four, five, or all of R', Y-2. S- R26 R. R. R. R', and R are independently selected from hydrocarbon groups, and particularly, those hydrocarbon N N R29 R25 groups containing at least one, two, or three carbonatoms and 35 up to four, five, six, seven, or eight carbonatoms (e.g., methyl, ethyl, n-propyl, isopropyl. n-butyl, isobutyl, sec-butyl, t-bu tyl, n-pentyl, isopentyl, neopentyl, n-hexyl, n-heptyl, n-octyl, Informula (6f),R,R,R,R,R,R,R7, R, and R’ isooctyl, phenyl, benzyl, and tolyl groups). In other embodi are each independently selected from a hydrogen atom and ments of formula (7), at least one of R. R. R. R. R. any of the Substituted or unsubstituted hydrocarbon groups 40 and R' (i.e., one, two, three, four, five, or all of R. R'7, R', described above. In particularembodiments, the hydrocarbon R', R', and R') is selected from amino groups according to groups independently contain at least one, two, or three car formula (1) and/or imino groups according to formula (1a) bon atoms and up to four, five, six, seven, or eight carbon and/or phosphaZeno groups according to formulas (1b), (1c), atoms (e.g., methyl, ethyl, n-propyl, isopropyl. n-butyl, (1d), and/or (1e). isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, 45 In the particular case when all of the shown amino groups n-hexyl, n-heptyl, n-octyl, isooctyl, phenyl, benzyl, and tolyl of formula (6) are phosphaZeno groups selected from formu groups). In one embodiment, R. R. R. R7, R, and R’ las (1b), (1c), (1d), and/or (1e), formula (6) encompasses are all hydrogen atoms. In other embodiments, one, two, phosphaZene species of the following chemical formula: three, four, or five, of R. R. R. R7, R, and R are hydrocarbon groups and the remainder are hydrogen atoms. 50 In another embodiment, R. R. R. R7, R, and Rare (8) all hydrocarbon groups. In further embodiments, one, two, or NEPR40R1R2 all of R. R. and R are hydrocarbon groups while one, two, or all of R. R. and R are hydrogen atoms. In still other embodiments, one, two, or all of R. R. and Rare 55 hydrogenatoms while one, two, or all of R. R', and Rare hydrocarbon groups. In formula (8), R0, R, R2, Rio, R, R2, Rio", Ri", In one embodiment, R. R. and R in formula (6f) are not and R'' are as defined under formula (5), i.e., independently interconnected. In other embodiments, R is interconnected selected from unsubstituted or heteroatom-substituted hydro with R', and/or R7 is interconnected with R', and/or R is 60 carbon groups, and/oramino groups according to formula (1), interconnected with R. The linking group resulting from and/or imino groups according to formula (1a), and/or phos interconnection between Rand R', and/or between R and phaZeno groups according to formulas (1b), (1c), (1d), and/or R’, and/or between R and R, can be any of the linking (1e). In a first set of embodiments, at least one (i.e., one, two, groups described above. Typically, these linking groups are three, four, five, six, seven, eight, orall) of R', R', R', R', dimethylene, trimethylene, or tetramethylene linkers. 65 R'', R', R'", R'", and R'" is selected from hydrocarbon In particular embodiments of formula (6), at least one of groups. In a second set of embodiments, at least one (i.e., one, the shown amino groups (i.e., one, two, or all of NR'R''. two, three, four, five, six, seven, eight, orall) of R', R', R', US 8,524,388 B2 15 16 R', R', R', R', R'", and R'" is selected from amino includes the phosphorus atom shown in formula (9) and one groups according to formula (1). In a third set of embodi or more nitrogen atoms of the one or more amino, imino, ments, at least one (i.e., one two three, four, five, six, seven, and/or phosphaZeno groups. eight, or all) of R,R,R,R,R, R2, R", R", and For formula (9), one of R7, R77, and R7 can be a different R" is selected from imino groups according to formula (1a). kind of imino group than the type shown informula (1a), i.e., In a fourth set of embodiments, at least one (i.e., one, two, wherein one of R' or R' of formula (1) functions as an three, four, five, six, seven, eight, orall) of R', R', R. R', additional bond to the phosphorus atom in formula (9). Such R. R. R', R', and R'" is selected from phosphazeno an imino group can be depicted as follows: groups according to formulas (1b), (1c), (1 d), and/or (1e). In addition, any two or more of R, R', R. R. R. R. 10 =N R' (10) R", R', and R'" may beinterconnected. For example, two In formula (10), R is a hydrogen atom or any of the or three of R', R', and R', and/or two or three of R. R', hydrocarbon groups described above, including unsubsti and R', and/or two or three of R", R', and R', may be tuted and heteroatom-Substituted hydrocarbon groups, as interconnected. described under formula (1). In further embodiments of formulas (2) and (2a), the group 15 In particular embodiments, R of formula (2) or (2a) is a R" is a phosphorus-containing group that attaches to the nitro phosphorus-containing group (specifically, a phosphaZeno gen atom shown in formula (2) or (2a) by a phosphorus atom group) having the following formula: of the phosphorus-containing group. The phosphorus atom in the phosphorus-containing group can be, for example, any of the heteroatom-substituted hydrocarbon groups described (11) above wherein at least one of the heteroatoms is a phosphorus R30R31N atom that attaches to the nitrogen atom shown in formula (2) or (2a). The phosphorus-containing group can be, for R3N=P- example, an organophosphine or organophosphonium group. R32R33N In a particular embodiment, R is a phosphorus-containing 25 group of the formula: In formula (11), R. R. R', R, and Rare indepen dently selected from a hydrogen atom or any of the unsubsti tuted or heteroatom-Substituted hydrocarbon groups (9) described above, and particularly, those hydrocarbon groups R76 30 containing at least one, two, or three carbon atoms and up to four, five, six, seven, or eight carbon atoms (e.g., methyl, ethyl, n-propyl, isopropyl. n-butyl, isobutyl, sec-butyl, t-bu tyl, n-pentyl, isopentyl, neopentyl, n-hexyl, n-heptyl, n-octyl, isooctyl, phenyl, benzyl, and tolyl groups). Optionally, two or In formula (9) above, R7, R77, and R7 are each indepen 35 three of R. R. R', R, and Rare interconnected. dently selected from any of the unsubstituted or heteroatom When the phosphazeno group of formula (11) is included substituted hydrocarbon groups described above and bound in place of R in formula (2a), formula (2a) encompasses to the shown Patom by a carbon atom; and/or amino groups phosphaZene species of the following chemical formula: of formula (1) bound to the Patom shown in formula (9) by the nitrogenatom shown informula (1); and/or imino groups 40 of formula (1a) bound to the Patom shown in formula (9) by (12) the nitrogen shown in formula (1a); and/or phosphaZeno groups of formulas (1b), (1c), (1d), and/or (1e) bound to the P atom shown informula (9) by the nitrogen shown informulas (1b), (1c), (1 d), and/or (1e). In a particular embodiment, a 45 provision is made that, when t is 0, at least one (i.e., one, two, or all) of R', R, and R is selected from amino groups In formula (12), R. R. and Rare as defined under for according to formula (1) and/or imino groups according to mula (2a), including exemplary embodiments provided formula (1a) and/or phosphaZeno groups according to formu therein. The groups R. R. R', R, and Rare as defined las (1b), (1c), (1 d), and/or (1e). 50 under formula (11). In one embodiment, R7, R77, and R7 of formula (9) are When the phosphazeno group of formula (11) is included not interconnected. In another embodiment, two of R7, R77. in place of R' in formula (3a), formula (3a) encompasses and R' of formula (9) are interconnected by one or more phosphaZene species of the following chemical formula: covalent chemical bonds (e.g., carbon-carbon, carbon-oxy gen, and/or carbon-nitrogen bonds). When two of R. R', 55 and R are interconnected, a phosphorus-containing ring (13) results, which includes the phosphorus atom shown in for R30R3 IN NRSR6 mula (9). In another embodiment, all of R7, R77, and R7 of RN=P-N=P-NR7R H" formula (9) are interconnected by covalent chemical bonds. R32R33N NR9R 10 When all of R', R', and Rare interconnected, a phospho 60 rus-containing bicyclic ring system results, which includes the phosphorus atom shown informula (9). When one or more In formula (13), R. R. R. R. R. and R'' are as defined of R7, R77, and R7 are selected from amino groups, and/or under formula (3a), including exemplary embodiments pro imino groups, and/or phosphaZeno groups (i.e., according to, vided therein. The groups R. R. R', R, and Rare as respectively, formulas (1), (1a), or (1b)), an interconnection 65 defined under formula (11). In different embodiments, the of two or three of R7, R77, and R7 results, respectively, in a shown amino groups (i.e., one, two, three, four, or all of phosphaZene-containing ring or bicyclic ring system, which NRR, NR7R, NR'R'', NR'R'', and US 8,524,388 B2 17 18 —NRR) can be independently selected from amino tuted or heteroatom-Substituted hydrocarbon groups groups according to formula (1), and/or imino groups accord described above, and particularly, those hydrocarbon groups ing to formula (1a), and/or phosphaZeno groups according to containing at least one, two, or three carbon atoms and up to formulas (1b), (1c), (1 d), and/or (1e). Optionally, any two or four, five, six, seven, or eight carbon atoms (e.g., methyl, more groups selected from R. R. R. R. R. R. R. R', 5 ethyl, n-propyl, isopropyl. n-butyl, isobutyl, sec-butyl, t-bu R°, R, and Rare interconnected. For example, in differ tyl, n-pentyl, isopentyl, neopentyl, n-hexyl, n-heptyl, n-octyl, ent embodiments, two or more of R. R. R. R. R. and R' isooctyl, phenyl, benzyl, and tolyl groups). In a particular are interconnected, and/or R' and R are interconnected, embodiment, R. R. R. R. and R are all hydrogen and/or R and Rare interconnected, and/or two or more of atoms. In other embodiments, a provision is made that R', R. R. R', R, and Rare interconnected. 10 R", R', R, and R' cannot all be hydrogen atoms (or that In further embodiments of formula (13), R therein can be at least one of R. R. R', R, and R is a hydrocarbon a phosphorus-containing group as exemplified by formulas group). In a particular set of embodiments, R is a hydrogen (9) and (11). In the particular embodiment when R is a atom while one, two, three, or all of R. R. R', and Rare phosphorus-containing group according to formula (11), for 15 hydrocarbon groups, and particularly, methyl, ethyl, n-pro mula (13) encompasses phosphaZene species of the following pyl, and/or isopropyl groups. In other embodiments, a provi chemical formula: sion is made that R is not a hydrogenatom (or that R is a hydrocarbon group). In other embodiments, a provision is made that if R is a hydrogen atom, then R. R. R', and (14) R cannot all be methyl groups (or alternatively, if R', R', R°, and Rare all methyl groups, then R is not a hydrogen atom). In another particular set of embodiments, R. R', R. R. and R are all hydrocarbon groups, and particu larly, methyl, ethyl, n-propyl, and/or isopropyl groups. 25 Optionally, two or more of R. R. R., R., and R are In formula (14), R. R. R. R. R. and R'' are each interconnected, thereby resulting in a cyclic or polycyclic independently selected from a hydrogen atom and any of the (e.g., bicyclic, tricyclic, or higher cyclic) guanidinium spe Substituted or unsubstituted hydrocarbon groups, as defined cies. The hydrogen ion depicted in formula (15) by the sym under formula (3), including exemplary embodiments pro bol H" is typically attached to one or more of the nitrogen vided therein. The groups R. R. R., and R are as 30 atoms of the chemical structure, and more typically, to the defined under formula (11). The groups R. R. R. R. nitrogen atom attached to R. and R are each independently selected from hydrogen In particular embodiments of formula (15), RandR'' are atoms and any of the hydrocarbon groups described above, as interconnected. The resulting cyclic guanidinium species are described under formula (3), including exemplary embodi encompassed by the following chemical formula: ments provided therein. Optionally, any two or more groups 35 selected from R. R. R7, R,R,R,R,R, R2, R, R, R. R. R. and R are interconnected. For example, in different embodiments, two or more of R,R,R,R,R, and (16) R" are interconnected, and/or R' and R are intercon nected, and/or R° and Rare interconnected, and/or two or 40 more of R. R. R. R. and R are interconnected. In different embodiments, the shown amino groups (i.e., one, two, three, four, or all of NRR, NR7R, NR'R'', NROR3, NR2R3, NRSR, and NR7R) Ca be independently selected from amino groups according to 45 formula (1), and/or imino groups according to formula (1a). In formula (16), R. R. and R are as defined under and/or phosphaZeno groups according to formulas (1b), (1c), formula (15), including exemplary embodiments provided (1d), and/or (1e). The phosphazene species of formula (14) therein. The curve shown informula (16) represents a linking can represent further extended phosphaZene species by mak group that interconnects the two shown nitrogen atoms. The ing R a phosphorus-containing group (as exemplified by 50 linking group includes any of the unsubstituted or heteroa formula (9) and (11)), in the manner described above for R' in tom-Substituted hydrocarbon linking groups described formula (2a). The resulting phosphaZene species can be fur above, and particularly, those containing 2, 3, or 4 carbon ther extended any number of times in similar fashion such that atoms (particularly, ethylene, trimethylene and tetramethyl the number of N=P - backbone repeating units can num ene linkers). In aparticularembodiment, R. R. and Rare ber 5, 6, 7, 8, 9, or 10, or higher. 55 all hydrogen atoms. In other embodiments, a provision is In another embodiment, BH has a guanidinium composi made that R. R. and R' cannot all be hydrogenatoms (or tion within the following generic formula: that at least one of R. R. and R is a hydrocarbon group). In a particular set of embodiments, R is a hydrogen atom while one or both of R and Rare hydrocarbon groups, and (15) 60 particularly, methyl, ethyl, n-propyl, and/or isopropyl groups. NR50R51 In other embodiments, a provision is made that R is not a hydrogenatom (or that R is a hydrocarbon group). In other embodiments, a provision is made that if R is a hydrogen atom, then R and R cannot both be methyl groups. In 65 another particular set of embodiments, R, R, and Rare In formula (15), R. R. R., R., and Rare indepen all hydrocarbon groups, and particularly, methyl, ethyl, dently selected from a hydrogen atom or any of the unsubsti n-propyl, and/or isopropyl groups. US 8,524,388 B2 19 20 In particular embodiments of formula (16), the linker is a trimethylene linker, thereby resulting in cyclic guanidinium (18) species encompassed by the following chemical formula: 5 OOt (16a)

In formula (18), R is a hydrogen atom or hydrocarbon 10 group, as defined under formula (15) above, including exem plary embodiments therein. The curves shown informula (18) represent linking groups that interconnect the shown nitrogen atoms. The linking groups can independently be any of the unsubstituted or heteroatom-substituted hydrocarbon linking In formula (16a), R, R, and R are as defined under 15 groups described above, and particularly, those containing 2. formulas (15) and (16), including exemplary embodiments 3, or 4 carbon atoms (particularly, ethylene, trimethylene and provided therein. tetramethylene linkers). In particular embodiments of for In separate particular embodiments of formula (15), R mula (18), at least one of the two linkers is a trimethylene and Rare interconnected. The resulting cyclic guanidinium linker. species are encompassed by the following chemical formula: In particularembodiments of formula (18), both linkers are trimethylene linkers, thereby resulting in cyclic guanidinium species encompassed by the following chemical formula: (17) 25 (18a)

30 In formula (17), R. R', and R are as defined under formula (15), including exemplary embodiments provided In formula (18a), R is a hydrogen atom or hydrocarbon therein. The curve shown informula (17) represents a linking group, as defined under formula (15) above, including exem group that interconnects the two shown nitrogen atoms. The 35 plary embodiments therein. linking group includes any of the unsubstituted or heteroa In other particular embodiments of formula (15), one or tom-Substituted hydrocarbon linking groups described both of the shown amino groups (i.e., one or both of above, and particularly, those containing 2, 3, or 4 carbon - NR'R'' and - NRR) independently represent an atoms (particularly, ethylene, trimethylene and tetramethyl imino group of formula (1a). In a particular set of embodi ene linkers). Inaparticularembodiment, R,R, and Rare 40 ments, both aforesaid amino groups are imino groups, and the all hydrogen atoms. In other embodiments, a provision is resulting guanidinium species are encompassed by the fol made that R, R, and R cannot all be hydrogenatoms (or lowing formula: that one, two, or all of R', R, and R are hydrocarbon groups). In another particular set of embodiments, R. R. and Rare all hydrocarbon groups, and particularly, methyl, 45 (19) ethyl, n-propyl, and/or isopropyl groups. R 16 In particular embodiments of formula (17), the linker is a trimethylene linker, thereby resulting in cyclic guanidinium RSNE / RI 7 species encompassed by the following chemical formula: 50

(17a) RI R51 1. R52 H" 55 Informula (19) above, R. R'7, R', and Rare as defined ON under formula (4), i.e., independently selected from a hydro gen atom, and/or Substituted or unsubstituted hydrocarbon groups (including phosphorus-containing groups of formulas (9) and (11)), and/or amino groups of formula (1), and/or 60 imino groups of formula (1a), and/or phosphaZeno groups of In formula (17a), R, R', and Rare as defined under formulas (1b), (1c), (1d), and/or (1e), as described above. All formula (15), including exemplary embodiments provided exemplary embodiments given under formula (4) for R', therein. R7, R', and R'' are applicable herein. The group R is as In a further embodiment of formula (17a), R and R* are defined under formula (15), i.e., selected from a hydrogen additionally interconnected. The resulting bicyclic guani 65 atom or any of the unsubstituted or heteroatom-substituted dinium species are encompassed by the following chemical hydrocarbon groups described above. Optionally, two or formula: more of R. R. R. R', and R are interconnected as US 8,524,388 B2 21 22 described above. For any interconnection that occurs under groups are phosphaZeno groups, and the resulting guani formula (19), any one or more of the groups R. R. R. dinium species are encompassed by the following formula: R', and R' can be a linking bond (i.e., instead of a group) that links with a group, thereby allowing the resulting linker to contain as few as one carbon atom (e.g., —CH2—, or 5 - Toto 40 to 41D 42 (19b) =CH-) or a heteroatom (e.g., —O—, or —N=). =PR RIR In a particular set of embodiments of formula (19), each of R54N=C oH' the groups R. R. R', and Rare amino groups according Y= PR40'R41'R42' to formula (1). The resultingguanidinium species are encom passed by the following chemical formula: 10 In formula (19b) above, R, R', R. R. R', and R' it are as defined under formula (8), i.e., independently (19a) selected from unsubstituted or heteroatom-substituted hydro NR55R56 carbon groups, and/oramino groups according to formula (1), N and/or imino groups according to formula (1a), and/or phos / NR57R58 phaZeno groups according to formulas (1b), (1c), (1 d), and/or RSNEC oH' (1e). All exemplary embodiments given under formula (8) for \ NR59R60 R. R. R. R. R', and R'' are applicable herein. The NF group R is as defined underformula (15). Optionally, two or 2 more of R, R, R2, R, R, R2, and Rare intercon nected as described above. For any interconnection that occurs under formula (19b), any one or more of the groups In formula (19a), R, R, R, R57, R, R, R, R, R", R', R. R. R. R', and R can be a linking bond and R'' are each independently selected from a hydrogen (i.e., instead of a group) that links with a group, as described atom or any of the unsubstituted or heteroatom-substituted ° above under formula (19). hydrocarbon groups described above, and particularly, those In a particular set of embodiments of formula (19b), each hydrocarbon groups containing at least one, two, or three of the groups R. R. R. R. R', and R'' are amino carbon atoms and up to four, five, six, seven, or eight carbon groups according to formula (1). The resulting guanidinium atoms (e.g., methyl, ethyl, n-propyl, isopropyl. n-butyl, 30 species are encompassed by the following chemical formula: isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, n-heptyl, n-octyl, isooctyl, phenyl, benzyl, and tolyl groups). In a particular embodiment R. R. R. R. R. (19c) R. R. R', and R are all hydrogen atoms. In other NR63R64 embodiments, a provision is made that R. R. R. R7, 35 NFP-NR6R66 R. R. R', R', and R' cannot all be hydrogenatoms (or 668 that at least one of R,R,R, R57, R,R,R,R, and RSNEC N. oH' R is a hydrocarbon group). In a particular set of embodi- \ ments, R is a hydrogen atom while one, two, three, four, NFP-NR7R72 five, six, seven, or all of R. R. R7, R,R,R,R, and 40 NR73R74 R" are hydrocarbon groups, and particularly, independently selected from methyl, ethyl, n-propyl, and/or isopropyl groups. In other embodiments, a provision is made that Ris In formula (19e), RS, R, R, RS, R, R-7, R, R, not a hydrogen atom (or that R is a hydrocarbon group). In R', R7, R', R', and Rare independently selected from a another particular set of embodiments, R. R. R. R. 45 hydrogen atom or any of the unsubstituted or heteroatom R. R. R. R', and Rare all hydrocarbon groups, and Substituted hydrocarbon groups described above, and particu particularly, methyl, ethyl, n-propyl, and/or isopropyl groups. larly, those hydrocarbon groups containing at least one, two, Optionally, two or more of R, R, R, R7, R. R. R. or three carbonatoms and up to four, five, six, seven, or eight R', and Rare interconnected, thereby resulting in a cyclic carbon atoms (e.g., methyl, ethyl, n-propyl, isopropyl. n-bu or polycyclic (e.g., bicyclic, tricyclic, or higher cyclic) guani- 50 tyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, neopen dinium species. For any interconnection that occurs under tyl, n-hexyl, n-heptyl, n-octyl, isooctyl, phenyl, benzyl, and formula (19a), any one or more of the groups R. R. R. tolyl groups). In a particular embodiment, R. R. R. R. R7, R. R. R. R', and R can be a linking bond (i.e., R, R-7, R, R, R79, R7, R7, R7, and R7 are all hydro instead of a group) that links with a group, as described above gen atoms. In other embodiments, a provision is made that under formula (19). ss RS, R,R,R,R,R07, R8, R, R70, R7, R72, R78, and Any one two three or all of the above amino groups Rare not all hydrogenatoms (or that at least one of R. R. NR55R56, NRS7Rs, NR59Roo, and NR'R' of for- R64, R65, R66, R67, R68, R69, R70, R7, R72, R73, and R is a mula (19a) can also be imino groups according to formula hydrocarbon group). In a particular set of embodiments, R' (1a). Any one, two, three or all of the above amino groups is a hydrogenatom while one, two, three, four, five, six, seven, NRR, NR7R, NR'R'', and NR'R' can 60 eight, nine, ten, eleven, or all of R. R. R. R. R7, R, also be phosphaZeno groups selected from formulas (1b). R. R', R', R7, R', and R'' are hydrocarbon groups, and (1c), (1d), and/or (1e). particularly, methyl, ethyl, n-propyl, and/or isopropyl groups. In other particular embodiments of formula (15), one or In other embodiments, a provision is made that R is not a both of the shown amino groups (i.e., one or both of hydrogen atom (or that R is a hydrocarbon group). In -NR'R'' and NR-R) independently representaphos- 65 another particular set of embodiments, R. R. R. R. phaZeno group selected from formulas (1b), (1c), (1 d), and/or R, R7, R8, R, R70, R7, R72, R78, and R7 are all hydro (1e). In a particular set of embodiments, both aforesaid amino carbon groups, and particularly, methyl, ethyl, n-propyl, and/ US 8,524,388 B2 23 24 or isopropyl groups. Optionally, two or more of R. R. R. fluoride, chloride, bromide, and iodide), carbonate, bicarbon R65, R66, R67, R68, R69, R70, R71, R72, R73, and R74 a ate, the carboxylates (e.g., formate, acetate, propionate, interconnected, thereby resulting in a cyclic or polycyclic butyrate, Valerate, lactate, pyruvate, oxalate, malonate, glut (e.g., bicyclic, tricyclic, or higher cyclic) guanidinium spe arate, adipate, decanoate, and fluorocarboxylates, e.g., trif cies. For any interconnection that occurs under formula (19C), luoroacetate), hexafluorophosphate (PF), hexachlorophos any one or more of the groups R. R. R. R. R. R7, phate (PCl), perchlorate, chlorate, chlorite, perbromate, R. R. R. R', R7, R7, and R' can be a linking bond bromate, bromite, periodiate, iodate, dicyanamide (i.e., (i.e., instead of a group) that links with a group, as described N(CN)), the alkoxides (e.g., methoxide, ethoxide, isopro above under formula (19). poxide, phenoxide, and fluoroalkoxides, e.g., CFO), the Any one, two, three, four, five, or all of the above amino 10 amides (e.g., dimethylamide and diisopropylamide), diketo groups NR6R6, NRCSR06, NR67R68, NR69R70, nates (e.g., acetylacetonate), aluminum chlorides (e.g., -NR'R'', and —NR'R'' of formula (19c) can also be Al2Cl, AlCl4, and AlF), aluminum bromides (e.g., imino groups according to formula (1a). Any one, two, three AlBra), nitrate, nitrite, sulfate, bisulfate, sulfite, bisulfate, or all of the above amino groups —NR'R'', NR'R'', the sulfonates (e.g., CHSO, CHCHSO, CH (CH), NR7R, NRR79, NR7R72, and NR7R7 can 15 SO, benzenesulfonate, toluenesulfonate, dodecylbenzene also be phosphaZeno groups selected from formulas (1b). Sulfonate, and the like), phosphate, hydrogenphosphate, (1c), (1d), and/or (1e). dihydrogenphosphate, pyrophosphate, phosphite, arsenate, For the guanidinium species encompassed under formula hydrogenarsenate, dihydrogenarsenate, selenate, tellurate, (15), and subformulas more limited in scope, group R can tungstate, molybdate, chromate, silicate, the borates (e.g., also be a phosphorus-containing group. Such as exemplified borate, diborate, triborate, tetraborate, and tetrafluoroborate), by formulas (9) and (11). When the phosphazeno group of anionic borane, carborane clusters (e.g., BioHo and formula (11) is included in place of R in formula (15), BiH), perrhenate, permanganate, ruthenate, perruthen formula (15) encompasses guanidinium-phosphaZene spe ate, and the polyoxometallates. Organic derivatives of any inorganic species described cies of the following chemical formula: above are also contemplated for A. Some examples of these 25 types of species include the organoborates (e.g., BRRRR, wherein R. R. R. Rare typically hydrocar (19d) bon groups containing 1 to 6 carbon atoms), the alkylsulfates NR50R51 (e.g., diethylsulfate), alkylphosphates (e.g., ethylphosphate or diethylphosphate), and the phosphinates (e.g., bis-(2,4,4- 30 trimethylpentyl)phosphinate). In a particular embodiment, the species A of the ionic liquid is derived from a superacid HA. As generally under Informula (19d), R. R. R', and Rare independently stood in the art, the term 'superacid as used herein is gener selected from a hydrogen atom or any of the unsubstituted or ally understood to mean an acid having an acidity greater than heteroatom-Substituted hydrocarbon groups, as described 35 (or pKa less than) conventional mineral , and particu above underformula (15), including exemplary embodiments larly, an acidity greater than (or pKa less than) pure (i.e., provided therein. The groups R. R. R', R, and Rare 100%) . As 100% sulfuric acid is known to have as defined under formula (11). The group R can also be a a pKa of -3, the considered herein preferably phosphaZeno group according to formulas (9) or (11). possess a pKa of less than -3. For example, in different Any one, two, three, or all of the above amino groups 40 embodiments, it may be preferred for the superacid to have a NR'R'', NRR, NR'R'', and NRR in for pKa of or less than about -4, -5, -6, -7, -8, -9, -10, -11, mula (19d) can also be imino groups according to formula -12, -13, -14, -15, -16, -17, -18, -19, -20, -21, -22, -23, (1a). Any one, two, three or all of the above amino groups -24, or -25. In one embodiment, the Superacid does not NRORS, NR2R3, NROR, and NR2R3 in for contain fluorine atoms, while in another embodiment, the mula (19d) can also be phosphaZeno groups selected from Superacid contains one, two, three, or more fluorine atoms. formulas (1b), (1c), (1 d), and/or (1e). 45 Some of the acids enumerated above may possess a pKa of Optionally, two or more of R. R. R. R. R. R. less than -3, and hence, may also be Superacids. Some R. R. and R are interconnected, thereby resulting in a examples of known Superacids include fluorosulfonic acid cyclic or polycyclic (e.g., bicyclic, tricyclic, or higher cyclic) (FSOH), hexafluoroantimonic acid (HSbF), hexafluoro guanidinium species. For any interconnection that occurs arsenic acid (HASF), hexafluorotantalum acid (HTaF), and under formula (19d), any one or more of the groups R. R. 50 hexafluoroniobium acid (HNbF). The corresponding conju R. R. R. R. R. R. and R, can be a linking bond gate base species A of the foregoing Superacids are, respec (i.e., instead of a group) that links with a group, as described tively, fluorosulfonate (FSO), hexafluoroantimonate above under formula (19). (SbF), hexafluoroarsenate (ASF), hexafluorotantalate The conjugate base portion of the protic ionic liquid (i.e., (TaF), and hexafluoroniobate (NbF). species A) is any counteranion which, when associated with 55 In a particular set of embodiments, the species A of the the cationic component BH", permits the resulting ionic com protic ionic liquid has a formula within the general chemical pound to behave as an ionic liquid. As known in the art, the formula: composition and structure of the counteranion can have a significant effect on the properties (e.g., melting point, Vola tility, stability, viscosity, hydrophobicity, and so on) of the 60 (20) ionic liquid. O O In one embodiment, the species A of the ionic liquid is | - || derived from an acid HA. The acid HA can have any pKa value. In different embodiments, the corresponding species re-cr-its-ii-cis-cl.| A can be inorganic or organic, contain fluorine atoms or lack O O fluorine atoms, and be either symmetrical or asymmetrical in 65 structure. Some examples of common anionic species con In formula (20) above, Subscripts m and n are indepen sidered herein for A include, for example, the halides (e.g., dently 0 or an integer of 1 or above. Subscript p is 0 or 1, US 8,524,388 B2 25 26 provided that when p is 0, the group —N SO (CF), CF In a sixth set of embodiments of formula (21), m and n are Subtended by p is replaced with an oxide atom connected to independently at least 5 and up to 6, 7, 8, 9, 10, or 11. For the sulfur atom (S). example, in a particular embodiment, m is 5 while n is a value In one embodiment of formula (20), subscript p is 1, and of 5 or above (e.g., 5, 6, 7, 8, 9, 10, or 11). Some examples of thus, formula (20) reduces to the chemical formula: such anions include NSO,(CF). CF, CF (CF). SONSO(CF)CF, CF (CF). SONSO(CF). CF, CF (CF). SONSO(CF), CF, CF (CF). SONSO(CF) (21) CF, and so on. O O In a seventh set of embodiments of formula (21), m and n 10 are independently at least 6 and up to 7, 8, 9, 10, or 11. For example, in a particular embodiment, m is 6 while n is a value O O of 6 or above (e.g., 6, 7, 8, 9, 10, or 11). Some examples of Such anions include NSO(CF)CF, CF (CF) In one embodiment of formula (21), the shown perfluoro 15 SONSO,(CF). CF, CF (CF)SONSO,(CF)CF, CF, alkyl groups do not crosslink with each other, thereby result (CF)SONSO(CF)CF, CF (CF)SONSO(CF) ing in a non-cyclic anion. In a further embodiment, m and in CF, and so on. are the same number, thereby resulting in a symmetrical In an eighth set of embodiments of formula (21), m and in counteranion. In another embodiment, m and n are not the are independently at least 7 and up to 8, 9, 10, or 11. For same number, thereby resulting in an asymmetrical counter example, in a particular embodiment, m is 7 while n is a value anion. of 7 or above (e.g., 7, 8, 9, 10, or 11). Some examples of such In a first set of embodiments of formula (21), m and n are anions include NISO(CF),CF, CF (CF),SONSO independently at least 0 and up to 1,2,3,4,5,6,7,8,9, 10, or (CF)CF, CF (CF),SONSO(CF)CF, CF (CF), 11. When m and n are both 0, the resulting anion has the SONSO(CF)CF, and CF (CF),SONSO(CF) CF. formula CFSONSOCF, i.e., bis(trifluoromethylsulfonyl) 25 In other embodiments of formula (21), in abides by one or imide, or Tf.N. In another embodiment, mand n are not both a number of alternative conditions set forth in one of the 0. For example, in a particular embodiment, m is 0 while n is foregoing eight embodiments while in abides by one or a a value of 1 or above (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11). number of alternative conditions set forth in another of the Some examples of Such anions include foregoing eight embodiments. 30 In yet another embodiment of formula (21), the two fluo CFSONSOCFCF CFSONSO(CF)CF, roalkyl chains shown therein are crosslinked to form a cyclic CFSONSO(CF),CF, CFSONSO,(CF)CF, anion structure (i.e., along with removal of two fluorine CFSONSO(CF)CF, and so on, wherein it is understood atoms). In a particular embodiment, the cyclic anion has a that, in the foregoing examples, the negative sign indicative of formula within the following generic formula: a negative charge (i.e., '-') in the anion has been omitted for the sake of clarity. 35 In a second set of embodiments of formula (21), m and in (22) are independently at least 1 and up to 2, 3, 4, 5, 6, 7, 8, 9, 10. FC-SO or 11. For example, in a particular embodiment, m is 1 while (F2-y é N o n is a value of 1 or above (e.g., 1,2,3,4,5,6,7,8,9, 10, or 11). 40 M Some examples of such anions include NSOCFCF (i.e., FC-SO “BETI), CFCFSONSO(CF)CF, CFCFSONSO, (CF)CF, CFCFSONSO(CF)CF, CFCFSONSO, Informula (22) above, subscript v preferably has a value of (CF)CF, and so on. 0, 1, or 2, to produce, respectively, a five-membered, six In a third set of embodiments of formula (21), m and n are 45 membered, or seven-membered ring. Though formula (22) is independently at least 2 and up to 3, 4, 5, 6, 7, 8, 9, 10, or 11. shown as an unbranched and Saturated cyclic system contain For example, in a particular embodiment, m is 2 while n is a ing difluoromethylene units, the cyclic anion can also be value of 2 or above (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11). Some branched (e.g., by the presence of —CH or CF groups) examples of such anions include NSO(CF)CF, CF and/or unsaturated (e.g., by the presence of a -CF=CF (CF)SONSO(CF)CF, CF (CF)SONSO(CF). 50 group). CF, CF (CF)SONSO(CF)CF, and so on. In another embodiment, subscript p in formula (21) is 0, so In a fourth set of embodiments of formula (21), mand n are that formula (21) reduces to the chemical formula: independently at least 3 and up to 4, 5, 6,7,8,9, 10, or 11. For example, in a particular embodiment, m is 3 while n is a value of 3 or above (e.g.,3,4,5,6,7,8,9, 10, or 11). Some examples 55 (23) of such anions include NSO,(CF)CF, CF (CF). O SONSO(CF)CF, CF (CF)SONSO(CF). CF, CF (CF)SONSO(CF)CF, CF (CF)SONSO(CF), CF, and so on. O In a fifth set of embodiments of formula (21), m and n are 60 independently at least 4 and up to 5, 6, 7, 8, 9, 10, or 11. For In different exemplary embodiments of formula (23), m example, in a particular embodiment, m is 4 while n is a value can be 0 or above (e.g., up to 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11), of 4 or above (e.g., 4, 5, 6, 7, 8, 9, 10, or 11). Some examples 1 or above (e.g., up to 2,3,4,5,6,7,8,9, 10, or 11), 2 or above of Such anions include NSO(CF)CF, CF (CF) (e.g., up to 3, 4, 5, 6, 7, 8, 9, 10, or 11), 3 or above (e.g., up to SONSO(CF). CF, CF (CF)SONSO(CF)CF, CF 65 4, 5, 6, 7, 8, 9, 10, or 11), 4 or above (e.g., up to 5, 6, 7, 8, 9. (CF). SONSO(CF)CF, CF (CF). SONSO(CF). 10, or 11), 5 or above (e.g., up to 6, 7, 8, 9, 10, or 11), 6 or CF, and so on. above (e.g., up to 7, 8, 9, 10, or 11), 7 or above (e.g., up to 8, US 8,524,388 B2 27 28 9, 10, 11, or 12), 8 or above (e.g., up to 9, 10, 11, or 12), or 9 than, for example, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, or 1.8 g/mL, or or above (e.g., up to 10, 11, 12, 13, 14, 15, or 16). Some a particular range bounded by any two of the foregoing exem examples of such anions include CFSO (i.e., "triflate' or plary values. “TfG), CFCFSO, CF (CF)SO, CF (CF)SO, The Viscosity of the ionic liquid is typically no more than (i.e., “nonaflate” or “NfO), CF (CF)SO, CF (CF), 5 about 50,000 centipoise (50,000 cF) at an operating tempera SO, CF (CF)SO, CF (CF),SO, CF (CF)SO, ture of interest, and particularly at a temperature within CF (CF)SO, CF (CF)SO, CF (CF) SO, and so 20-30°C. In other embodiments, the viscosity of the ionic O. liquid can be about, at least, or no more than, for example, The protic ionic liquids described above, as well as the 25,000 cB, 10,000 cP,5,000 cP, 2,000 cP, 1,000 cB, 800cP, 700 10 cP 600 cP, 500 cP 400 cB, 300 cP, 200 cP, 120 cP 100 cP, or Superbase and acid components thereof, can be synthesized 50 cp. Alternatively, the viscosity of the ionic liquid may by procedures well-known in the art. For example, guanidino preferably be within a particular range bounded by any two of and phosphaZeno classes of described above can the foregoing exemplary values. be synthesized according to procedures described in A. A. The conductivity of the ionic liquid is typically at least 0.01 Kolomeitsev, et al., J. Am. Chem. Soc., 127, pp. 17656-17666 15 mS/cm (0.001 S/m) at an operating temperature of interest, (2005), which is herein incorporated by reference in its and particularly at a temperature within 20-30°C. In different entirety. The acids and Superacid component (HA or A) are embodiments, the conductivity of the ionic liquid can be generally well-known in the art, and numerous of them are about, at least, or no more than, for example, 0.01, 0.05, 0.1, commercially available. 0.2,0.3, 0.4,0.5, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, The protic ionic liquids described herein can be prepared 20 11.0. or 12.0 mS/cm, or a particular range bounded by any by any suitable method, including methods known in the art. two of the foregoing exemplary values. A general reference for the preparation, purification, and The superbase-derived ionic liquids described herein can testing of protic ionic liquids is found in T. L. Greaves, et al., also be combined with each other and/or with one or more Chem. Rev., 108, pp. 206-237 (2008), which is herein incor conventional ionic liquids, i.e., ionic liquids that are not porated by reference in its entirety. In a particular embodi- 25 Superbase-derived. The conventional ionic liquid can be, for ment, the ionic liquids described herein are prepared by direct example, any of the imidazolium-based ionic liquids known reaction of the acid HA and the superbase B in a suitable in the art (e.g., 1-butyl-3-methylimidazolium (BMIM) ionic Solvent. Such as a water or water-alcohol Solvent. In another liquids, such as BMIMITfNI), and/or any of the N-alky embodiment, particularly when HA is a Superacid, the ionic lpyridinium-based ionic liquids known in the art, and/or any liquids described herein are prepared in a two-step process 30 of the ammonium-based ionic liquids known in the art (e.g., EtNHTf.N., where Et indicates ethyl), and/or any of the wherein the superbase B is first reacted with a strong acid HA' phosphonium-based ionic liquids known in the art, and/or (e.g., a mineral acid) to form the species BHA', and then the piperidinium-based ionic liquids known in the art, and/or species BHA' is reacted with a salt of the superacid (i.e., pyrrolidinium-based ionic liquids known in the art, and/or MA, wherein M is a metal, such as an alkali metal) to form 35 Sulfonium-based ionic liquids known in the art. In particular BHA along with MA'. Typically, particularly when an embodiments, admixture of one or more of the above-de aqueous phase is utilized, the ionic liquid is less Soluble than scribed superbase-derived ionic liquids with another super the salt byproduct in water, and therefore, settles out of the base-derived ionic liquid or one or more conventional ionic Solution as a separate phase, thereby making separation pos liquids has the beneficial effect of lowering the melting point sible by use of for example, a separatory funnel. Because the 40 (i.e., fusion temperature or liquidus temperature, T) of the ionic liquid is generally more dense than the solvent, the ionic superbase-derived ionic liquid. This effect can be particularly liquid tends to form a lower phase while the salt byproduct is desired for lowering the melting point of a Superbase-derived maintained in a solvent upper phase. After the ionic liquid is ionic liquids that has a melting point above the typical upper initially separated, the ionic liquid can be purified by any of temperature of 100°C. The inclusion of one or more conven the means known in the art (e.g., Solvent washings and/or 45 tional ionic liquids may also serve to modify, adjust, or opti distillation). mize one or more other properties or characteristics of the The protic ionic liquids of the invention are naturally in a ionic liquid, including density, Viscosity, conductivity, liquid state (i.e., fluids) typically at or below 100° C., and chemical, or catalytic properties. In other embodiments, one more typically, at or below 90° C., 80° C., 70° C., 60° C., 50° or more particular classes or compositions of conventional C., 40°C., orator below room temperature (i.e., at or less than 50 ionic liquids are excluded from the ionic liquid composition, about 15, 20, 25, or 30°C.). In other embodiments, the ionic or alternatively, any ionic liquid not described herein as a liquids are in liquid form at or below 0°C., -5°C., -10°C., Superbase-derived ionic liquid is excluded. -20°C., or -30° C. Preferably, the ionic liquid possesses a The invention is also directed to compositions that include melting point that is at or below any of the temperatures given one or more of the above-described ionic liquids admixed above. Though the invention primarily contemplates ionic 55 with one or more solvents. The solvent can function, for liquids that are naturally fluids at or below room temperature, example, as a casting solvent, film-forming solvent, or the invention also contemplates ionic liquids that are solid or matrix. The solvent can be, for example, a polar protic Sol semi-solid at about room temperature or above (or at 100° C. vent, polar aprotic solvent, or a non-polar solvent. Some or above), but which can be rendered liquids at a higher examples of polar protic solvents include the alcohols con temperature by the application of heat. The latter embodiment 60 taining up to four linked carbon atoms (e.g., methanol, etha may be particularly suitable if the process in which the ionic nol, isopropanol, n-butanol, t-butanol), diols (e.g., ethylene liquid is used is a high temperature process (i.e., above room glycol, diethylene glycol, triethylene glycol), and protic temperature). amines (e.g., ethylenediamine, ethanolamine, diethanola The density of the ionic liquid is generally above 1.2 g/mL mine, triethanolamine). Some examples of polar aprotic Sol at an operating temperature of interest, and particularly at a 65 vents include the nitriles (e.g., acetonitrile, propionitrile), temperature within 20-30°C. In different embodiments, the Sulfoxides (e.g., dimethylsulfoxide), amides (e.g., dimethyl density of the ionic liquid can be about, at least, or no more formamide, N,N-dimethylacetamide), organochlorides (e.g., US 8,524,388 B2 29 30 methylene chloride, chloroform, 1,1-trichloroethane), into the Support or matrix material by either being homoge ketones (e.g., acetone, 2-butanone), dialkylcarbonates (e.g., neously incorporated therein, or alternatively, impregnated or ethylene carbonate, dimethylcarbonate, diethylcarbonate), infused into porous spaces of a Support material. In another organoethers (e.g., diethyl ether, tetrahydrofuran, and diox embodiment, the ionic liquid is a layer on a Support material. ane), HMPA, NMP, and DMPU. As used herein, a “non-polar In another embodiment, the ionic liquid is a layer sandwiched Solvent' is a solvent containing a linkage of at least five between layers of Support material. carbon atoms. Accordingly, some examples of non-polar Sol vents include n-pentanol, n-hexanol, a pentane, hexane, hep The film or membrane containing the ionic liquid can have tane, octane, pentene, hexene, heptene, octene, oran aromatic any suitable thickness. For example, in different embodi Solvent. Such as benzene, toluene, or a Xylene. In different 10 ments, the film or membrane can have a thickness of about, at embodiments, the solvent can be included in an amount of, or least, or no more than 1, 2, 3, 4, 5, 10, 20, 30, 40, 50, 60, 70, at least, or less than, for example, 0.1 wt %, 0.5 wt %, 10 wt 80, 90, 100,120, 140,160, 180, or 200 microns, or a thickness %, 20 wt %, 30 wt %, 40 wt %, 50 wt %, 60 wt %, 70 wt %, within a range bounded by any two of the foregoing values. 80 wt %, 90 wt % (by total weight of the ionic liquid, solvent, The ionic liquid and polymer matrix can be combined in and any other components), or within a range bounded by any 15 any suitable weight ratio. For example, in different embodi of the foregoing exemplary values. ments, the weight ratio of ionic liquid to polymer matrix is In other embodiments, one or more of any of the foregoing preferably about 5:95, 10:90, 20:80, 30:70, 40:60, 50:50, classes of Solvents, or specific solvents, is excluded. For example, in some embodiments, it may be preferable to 60:40, 70:30,80:20,90:10, or 95:5, or withina rangebounded exclude solvents having a boiling point over 25°C., 50°C., or by any two of the foregoing values. 100°C. In other embodiments, it may be preferable to exclude A film or membrane of the ionic liquid can be prepared by solvents having a boiling point under 25°C., 50° C., or 100° any of the means known in the art. For example, the film or C. In yet other embodiments, it may preferable to include only membrane can be prepared by mixing a matrix or Support one or more solvents in which the ionic liquid is Substantially material with the ionic liquid, often in combination with a soluble, or partially soluble, or Substantially insoluble (e.g., 25 casting solvent, and casting the mixture onto a desired Sub as separate phases). In a particular embodiment, all solvents strate. Typically, the initially casted layer is heated to remove are excluded. the casting solvent, thereby solidifying the layer. Other pro In one set of embodiments, the protic ionic liquids cesses, such as crosslinking reactions, can additionally be described above contain or are admixed with a certain amount employed to further solidify the film. of water, e.g., about, at least, or no more than 1%. 5%, 10%, 30 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90% of water. In Examples have been set forth below for the purpose of another set of embodiments, the ionic liquid is substantially illustration and to describe certain specific embodiments of devoid of water. For example, in some embodiments, it is the invention. However, the scope of this invention is not to be desirable that the ionic liquid contains less than 1% by weight in any way limited by the examples set forth herein. of water, or less than 0.5%, 0.1%, 0.01%, or even less than 35 0.001% by weight of water. Example 1 In another aspect, the invention is directed to applying the above-described protic ionic liquids as an ionic liquid-con taining films useful, for example, as proton exchange mem Preparation of Protic Ionic Liquids (PILs) brane materials or separation materials (i.e., that are perme 40 able or impermeable to a gas and/or a liquid. Such as in an Sixteen exemplary PILS were prepared by reacting Super industrial process). In a particular embodiment, the film or bases, as shown below, with either of two perfluoroalkylsul membrane is composed of solely one or more of the above fonamide superacids (specifically, either HTfN or HBETI). described ionic liquids. The eight superbases are as follows: In another embodiment, the film or membrane includes one 45 or more of the above-described ionic liquids in combination with a Support or matrix material. Depending on the desired application, the Support or matrix material can be an inert (i.e., non-reactive) material, or alternatively, a chemically reactive or physically active material. The Support or matrix 50 material can have any Suitable characteristics. Such as being N flexible or rigid, malleable or non-malleable, and porous or non-porous. A class of Support materials particularly consid 1 / -)---O ered herein are solid polymers, and particularly, those poly N=- mers Suitable for use as a membrane material in proton 55 \ exchange membrane or polymer electrolyte membrane 1N (PEM) fuel cells. A particular class of polymer support mate t-BuP1(dma) t-BuP1(pyrr) rials considered herein are the fluoropolymers, such as poly vinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), NN perfluoroalkoxy polymer resin (PFA), polyvinylfluoride 60 N1 (PVF), sulfonated forms thereof, and copolymers thereof. NEP-N\ N / Some examples of fluoropolymer-containing copolymers N HNEP-N include poly(vinylidenefluoride-co-hexafluoropropylene), Nafion, fluorinated ethylene-propylene, and poly(ethylene 1) 1NJ co-tetrafluoroethylene) (PTFE). 65 BEMP HP1(dma) In one embodiment, the ionic liquid is integrated within the Support or matrix material. The ionic liquid can be integrated US 8,524,388 B2 31 32 -continued TABLE 2 Thermal properties of superbase-derived PILs N- N1 Superbase This C. Tde C. 1=1--- NHE TiN beti TfN beti \ t-BuPI(dma) 130 108 324 321 t-BuP1(pyrr) 13 8: 323 322

1N 1 NS )) BEMP & 300 311 EtP2(dima) HNC(dma) 10 HP1(dma) 325 325 EtP(dma) 347 319 MTBD 379 383 HTBD 3.71 338 HNC(dma) 297 302 15 * T is the temperature of fusion measured from DSC and T is the decomposition COCOCH H temperature corresponding to a 10% mass loss measured using TGA, The shaded regions denote formulations that meet the arbitrary ionic liquid definition of possessing T values MTBD HTBD below 100° C. The unshaded T values represent borderline cases. As shown by Table 2, their thermal decomposition tem The new PILs were synthesized in high yield (>98%) via a peratures (T) of the eight shown PILs fall in the 300-380° single pot synthesis in two steps, as depicted in FIG.1. Refer C. range, which is considerably above the operating tempera ring to the PILMTBDHTf.N) for illustration, MTBD (pK ture of PEM fuel cells. With this in mind, selected PILs were (BH)=25.4) was initially dissolved in water and chilled in an tested at 150° C. for a period of several hours using TGA. ice bath, followed by careful titration with 10.6 NHNO to 25 These results are shown in FIG. 2 (see also FIG. 3). Clearly, form aqueous MTBDHINOI. Anion exchange was the weight losses of these superbase PILs are significantly achieved by adding one equivalent of LiTfN in water, result lower than those of conventional ammonium-based PILs ing in spontaneous segregation of the dense, lower MTBDH bearing the same anion, such as EtNHTf.N. Quite Tf.N. phase. After careful washing with double distilled remarkably, the superbase-derived PIL (MTBDHTf.N. water several times, rotary evaporation resulted in a nearly 30 exhibited kinetic TGA characteristics similar to that of colorless free-flowing PIL in nearly quantitative yield. In this BMIMTf2N (see FIG. 4). Moreover, based on the linear (Zero-order) evaporative mass losses for MTBDHTfNI at case, following vacuum drying at 70° C. overnight, MT several temperatures well below T. (FIG.5), an enthalpy of BDHTf.N contained some 110 ppm water (as determined vaporization, A.H. of 89 kJ mol' was estimated for this PIL by Karl-Fischer Coulometric titration) and showed a room 35 (FIG. 6), a number ca. 25% below the value determined for temperature ionic conductivity (o) of 1.49 mS cm. Some of BMIMITfN using the same isothermogravimetric the physical properties of three of the exemplary PILs are approach. shown in Table 1 below. Of the 16 newly synthesized PILs, only five possess melt ing points outside the classic ionic liquid range. However, TABLE 1. 40 even in these cases, the liquidus temperature can be greatly reduced by simple eutectic mixing with conventional AILS. Physical properties of selected PILs For instance, the borderline PIL (t-BuP1(dma)HIBETI), which has a T of 108° C., forms a liquid system near m/mPas' o(25° C.), ambient temperature when mixed with 28 vol % BMIM 45 TfNI (BMIM=1-butyl-3-methylimidazolium). The DSC PIL d/g cm 23° C. 40° C. 100° C. mS cm curves showing these results are given in FIG. 7. Example 3 MTBDHTf,N) 1.49 148 63 10.4 1.49 MTBDHbeti 1.52 421 139 14.2 O.70 50 Stability Analyses of the Protic Ionic Liquids HNC(dma)Hbeti 1.51 224 81.0 10.2 0.79 As illustrated in FIGS. 8A (before KOH addition) and 8B d is the mass density, m is the viscosity, and O is the ionic conductivity, (after KOH addition), MTBDHTfN (right vial) remains The uncertainty in m is approximately +5%. stable when contacted with 1.0 N KOH solution in the pres 55 ence of the indicator Nile Red, an observation consistent with the superbasicity of MTBD. In sharp contrast, for the conven tional PIL EtNHTfN (left vial), the biphase degrades Example 2 almost instantaneously to form an aqueous solution under these conditions, developing autogenous pressure during the Thermophysical Properties of the Protic Ionic 60 process if a sealed vessel is used. Using the positive Solvato Liquids chromic probe Nile Red (NR), it is also noted that the polarity of MTBDHTfN is somewhat lower than that of conven tional PILs such as EtNHITfN (Evalues are 214.0 and Select thermophysical properties of eight of the exemplary 209.1 kJ mol', respectively). This trend can be discerned by PILs are shown in Table 2 below. Both thermogravimetric 65 visual inspection of water/EtOH mixtures containing NR (TGA) and differential scanning calorimetry (DSC) testing (FIG. 8C). However, both PILs remain more polar than was performed on select exemplary PILs. BMIMTf2N which has an ENR akin to EtOH (218 kJ US 8,524,388 B2 33 34 mol). (Jin, H., et al., J. Phys. Chem. B 2008, 112, 81: (iv) phosphaZeno groups derived from formula (1) Ogihara, W., et al., Chem. Lett., 2004, 33, 1414: Carmichael, wherein R'' and R' together represent a double bond A., et al., J. Phys. Org. Chem. 2000, 13,591). This behavior is connecting the shown nitrogen atom to a phosphorus further evidenced by use of Thymol Blue (TB), as shown in atom, as depicted in the following chemical formula: FIG.9. As shown, EtNHTf,N (left vial) is clear whereas 5 MTBDH (Tf,N) is blue in presence of KOH and TB (wherein it is understood that TB is red to yellow at pH of (1b) 1.2-2.8 and yellow to blue at pH of 8.0-9.6). The foregoing is R40 evidence that EtNHTf,N has reacted with KOH whereas MTBDHTfN has not, thereby showing the greater stabil- 10 ity (i.e., lack of reactivity and resistance to degradation) of R42 MTBDHTf.N. While there have been shown and described what are at present considered the preferred embodiments of the inven wherein R', R' and Rare independently selected from tion, those skilled in the art may make various changes and 15 hydrocarbon groups, amino groups according to for modifications which remain within the scope of the invention mula (1), and imino groups according to formula (1a), defined by the appended claims. wherein said hydrocarbon groups are optionally and What is claimed is: independently substituted with one or more heteroatoms 1. An ionic liquid having a composition of formula (A) or heteroatom groups, and optionally, two or three of (BH") wherein A is a conjugate base of an acid HA, and BH' 20 R', R'' and R are interconnected to form a cyclic, is a conjugate acid of a Superbase B. bicyclic, or polycyclic phosphaZeno group; 2. The ionic liquid of claim 1, wherein BH has a compo R" is either a hydrogen atom or hydrocarbon group, sition according to the chemical formula: wherein said hydrocarbon groups are optionally and independently substituted with one or more heteroatoms 25 or heteroatom groups; (2) subscript t is 0 or 1, to indicate, respectively, the absence or RI presence of the group R N=, provided that when t is (R-N=4- R2.H. 0, at least one of R', R, and R is an amino group, imino group, or phosphaZeno group shown, respectively, by R3 30 formulas (1), (1a), and (1b); and optionally, two or more of R. R. and R are intercon wherein R', R, and R are each independently selected nected. from: 3. The ionic liquid of claim 2, wherein BH has a compo (i) hydrocarbon groups bound to P in formula (2) by a sition according to the chemical formula: carbon atom, wherein said hydrocarbon groups are 35 optionally and independently substituted with one or more heteroatoms or heteroatom groups; (3) (ii) amino groups bound to Pinformula (2) by a nitrogen NRSR6 atom, said amino group is according to the chemical (R-N3= P-NR7RS.H. formula: 40 NR9R 10 NRI2R13 (1) wherein R'' and R' are each independently selected from wherein R. R. R. R. R. R', and R'' are each indepen a hydrogen atom and hydrocarbon groups, wherein said dently selected from a hydrogen atom and hydrocarbon hydrocarbon groups are optionally and independently 45 group, wherein said hydrocarbon group is optionally Substituted with one or more heteroatoms or heteroatom and independently substituted with one or more heteroa groups, and optionally, R'' and R' are interconnected toms or heteroatom groups; to form a cyclic, bicyclic, or polycyclic amino group; optionally, two or more of R. R. R. R. R. and R' are (iii)imino groups derived from formula (1) wherein R' interconnected; and R' together represent a double bond connecting 50 optionally, one, two, or all of NR'R''. - NR'R', and the shown nitrogenatom to a carbonatom, as depicted —NR'R'' are independently selected from imino in the following chemical formula: groups of formula (1a) and/or phosphaZeno groups of formulas (1b); and subscript t is 0 or 1, to indicate, respectively, the absence or (1a) 55 presence of the group R' N—. R 14 4. The ionic liquid of claim 3, wherein at least one of -N=t^ - NRR, NR7R, and NR'R' is selected from imino V 15 groups of formula (1a) and/or phosphaZeno groups of formu R las (1b). 60 5. The ionic liquid of claim 3, wherein at least one of wherein R'' and Rare each independently selected from NRR, NR7R, and - NR'R'' is selected from phosp a hydrogen atom, hydrocarbon groups, and amino haZeno groups of formulas (1b). groups according to formula (1), wherein said hydrocar- 6. The ionic liquid of claim 3, wherein at least one of bon groups are optionally and independently substituted - NRR, NR7R, and NR'R' is selected from imino with one or more heteroatoms or heteroatom groups, and 65 groups of formula (1a). optionally, R'' and R'' are interconnected to form a 7. The ionic liquid of claim 6, wherein - NRR, cyclic, bicyclic, or polycyclic imino group; and - NR7R, and - NR'R'' are all independently selected from US 8,524,388 B2 35 36 imino groups of formula (1a), wherein BH has a composi tion according to the chemical formula: (4a) R 16

(4) 5 N 1. R17 R18 R-N-P N oHt N N R20 R19 10 R21 wherein R'', R, R7, R. R. R', and R are each independently selected from a hydrogen atom, hydro 15 carbon groups, amino groups according to formula (1), wherein R'', R, R7, R. R. R', and R are each imino groups according to formula (1a), and phosp independently selected from a hydrogen atom, hydro haZeno groups according to formula (1b), wherein said carbon groups, amino groups according to formula (1), hydrocarbon groups are optionally and independently imino groups according to formula (1a), and phosp Substituted with one or more heteroatoms or heteroatom haZeno groups according to formula (1b), wherein said groups; and optionally, two or three of R. R. R. hydrocarbon groups are optionally and independently R. R', and Rare interconnected. Substituted with one or more heteroatoms or heteroatom 14. The ionic liquid of claim 12, wherein at least one of R', groups: R7, R. R. R', and R is selected from amino groups optionally, two or three of R', R'7, R. R. R. and R' according to formula (1), imino groups according to formula are interconnected; and 25 (1a), and phosphaZeno groups according to formula (1b). t is 0 or 1, to indicate, respectively, the absence or presence 15. The ionic liquid of claim3, whereint is 0 such that BH' of the group R'' N=. has a composition according to the chemical formula: 8. The ionic liquid of claim 7, wherein at least one of R', R. R. R. R', and R is selected from amino groups (6) according to formula (1), imino groups according to formula 30 NRSR6 M (1a), and phosphaZeno groups according to formula (1b). P-NRRS-HT 9. The ionic liquid of claim 3, wherein BH has a compo sition according to the chemical formula: NR9R 10 35 wherein R. R. R. R. R. R', and R'' are each indepen (3a) dently selected from a hydrogen atom and hydrocarbon NRSR6 groups, wherein said hydrocarbon groups are optionally and independently substituted with one or more heteroa toms or heteroatom groups; 40 optionally, two or more of R. R. R. R. R. and R'' are interconnected; and wherein R. R. R. R. R. R', and R'' are each indepen optionally, one, two, or all of NRR, NR7R, and dently selected from a hydrogen atom and hydrocarbon —NR'R'' are independently selected from imino group, wherein said hydrocarbon group is optionally 45 groups of formula (1a) and/or phosphaZeno groups of and independently substituted with one or more heteroa formulas (1b). toms or heteroatom groups; 16. The ionic liquid of claim 15, wherein at least one of R optionally, two or more of R. R. R. R. R. and R'' are and R is interconnected with one or two of R. R. R. and interconnected; and R10. optionally, one, two, or all of NRR, NR7R, and 50 17. The ionic liquid of claim 15, wherein R. R. and R' —NR'R'' are independently selected from imino are interconnected. groups of formula (1a) and/or phosphaZeno groups of 18. The ionic liquid of claim 17, wherein BH has a com formulas (1b). position according to the chemical formula: 10. The ionic liquid of claim 9, wherein at least one of -NRR, NR7R, and NR'R' is selected from imino 55 groups of formula (1a) and/or phosphaZeno groups of formu (6f) las (1b). 11. The ionic liquid of claim 9, wherein at least one of —NRR, NR7R, and - NR'R'' is selected from phosp haZeno groups of formulas (1b). 60 12. The ionic liquid of claim 9, wherein at least one of -NRR, NR7R, and NR'R' is selected from imino groups of formula (1a). 13. The ionic liquid of claim 9, wherein - NRR, -NR'R', and NR'R'' are all independently selected from 65 wherein R, R7, R. R. R. R. R7, R, and Rare imino groups of formula (1a), wherein BH has a composi each independently selected from a hydrogen atom and tion according to the chemical formula: hydrocarbon groups, wherein said hydrocarbon groups US 8,524,388 B2 37 38 are optionally and independently substituted with one or 23. The ionic liquid of claim 3, wherein one, two, or all of more heteroatoms or heteroatom groups. - NRR, NR7R, and NR'R'' are independently 19. The ionic liquid of claim3, wherein at least one of R, selected from imino groups of formula (1a) and/or phosp R. R. R. R. R', and R'' is a phosphorus-containing group haZeno groups of formulas (1b). wherein a phosphorus atom contained therein is bound to a nitrogen atom shown in formula (3). 24. The ionic liquid of claim 3, wherein at least one of 20. The ionic liquid of claim 19, wherein said phosphorus - NRR, NR7R, and—NR'R'' is selected from phosp containing group has the following chemical structure: haZeno groups of formulas (1b). 25. The ionic liquid of claim 24, wherein all of NRR, 10 - NR7R, and - NR'R'' are independently selected from (11) phosphaZeno groups of formulas (1b) such that BH has a R30R31N composition according to the chemical formula:

15 (5) wherein R. R. R', R, and R are independently NEPR40R1R2 Selected from a hydrogenatom and hydrocarbon groups, wherein said hydrocarbon groups are optionally and independently substituted with one or more heteroatoms or heteroatom groups. 21. The ionic liquid of claim 20, wherein BH has a com wherein R0, R, R2, R0, R, R2, RO", R", and R2" are position according to the chemical formula: independently selected from hydrocarbon groups, amino groups according to formula (1), imino groups according to 25 formula (1a), and phosphaZeno groups according to formula (13) (1b), R is selected from a hydrogen atom and hydrocarbon R30R3 IN NRSR6 groups, wherein said hydrocarbon groups are optionally and independently substituted with one or more heteroatoms or heteroatom groups; t is 0 or 1; and optionally, two or more 30 groups selected from R,R,R,R,R,R,R,R'", R" and Rare interconnected. wherein R,R,R7, R,R,R,R,R,R,R, and R. are each independently selected from a hydrogen atom 26. The ionic liquid of claim25, wherein at least one of R', and hydrocarbon groups, wherein said hydrocarbon R,R,R,R, R2, R", R", and R2" is selected from groups are optionally and independently substituted 35 said amino groups. with one or more heteroatoms or heteroatom groups, and 27. The ionic liquid of claim 25, wherein R', R', R, optionally, the shown amino groups —NR'R''. R9, R, R2, R", R", and R'2" are independently NR7R, NR'R'', NR'R'', and NRR are selected from said amino groups. independently selected from imino groups of formula (1a) and/or phosphaZeno groups of formulas (1b), and 28. The ionic liquid of claim 25, whereint is 0 such that optionally, any two or more groups selected from R. R. 40 BH has a composition according to the chemical formula: R7, R. R. R. R. R. R. R., and Rare inter connected. 22. The ionic liquid of claim 21, wherein R is substituted with a phosphorus-containing group of formula (11) Such that 45 BH" has a composition according to the chemical formula:

(12) 50 wherein R40 R41 R42 R40' R41 R42 R40" R41" and R42 are as defined in claim 25. 29. The ionic liquid of claim 25, whereint is 1 such that BH has a composition according to the chemical formula: wherein R, R, R7, R. R. R. R. R. R. R. R. 55 R. R7, R, and Rare each independently selected from a hydrogenatom and hydrocarbon groups, wherein (14) said hydrocarbon groups are optionally and indepen NEPR40RR2 dently substituted with one or more heteroatoms or het eroatom groups, and optionally, the shown amino 60 groups NRR, NR7R, NR'R'', NR'R'', NRR, NRR, and NR7R are indepen dently selected from imino groups of formula (1a) and/ wherein R*0, R*, R2, R10',R,R'2, Rio", R", R'2" and orphosphaZeno groups of formulas (1b), and optionally, Rare as defined in claim 25. any two or more groups selected from R,R,R,R,R, 65 R10, R30, R3, R32, R33, R35, R36, R37, R3s, and R39 a 30. The ionic liquid of claim 1, wherein BH has a com interconnected. position according to the chemical formula: US 8,524,388 B2 39 40 wherein R, R', and Rare as defined in claim 30, and (15) the curve shown in the formula represents a linking NR50R51 group that interconnects the two shown nitrogen atoms. 34. The ionic liquid of claim 33, wherein said linker is a 5 trimethylene linker such that BH has a composition accord ing to the chemical formula: wherein R,R,R', R, and Rare eachindependently Selected from a hydrogen atom, hydrocarbon groups, (17a) and phosphorus-containing groups of formula (11), 10 R51 wherein said hydrocarbon groups are optionally and independently substituted with one or more heteroatoms or heteroatom groups; Oals R52. Hit optionally, one or both of NR'R'' and - NR'R'' are N r independently selected from imino groups of formula 15 (1a) and/or phosphaZeno groups of formula (1b); and optionally, two or more of R. R. R', R, and R' wherein R, R, and Rare each independently selected are interconnected. from a hydrogen atom, hydrocarbon groups, and phos 31. The ionic liquid of claim 30, wherein BH has a com phorus-containing groups of formula (11), wherein said position according to the chemical formula: hydrocarbon groups are optionally and independently Substituted with one or more heteroatoms or heteroatom (16) groups. 35. The ionic liquid of claim 30, wherein BH has a com 25 position according to the chemical formula:

(18) 30 Out wherein R', R, and Rare as defined in claim 30, and N the curve shown in the formula represents a linking group that interconnects the two shown nitrogen atoms. 32. The ionic liquid of claim 31, wherein said linker is a 35 trimethylene linker, such that BH has a composition accord ing to the chemical formula: wherein R is as defined in claim 30, and each curve shown in the formula independently represents a linking 40 group that interconnects two shown nitrogen atoms. (16a) 36. The ionic liquid of claim 35, wherein said linkers are both trimethylene linkers such that BH has a composition according to the chemical formula:

45 (18a)

wherein R, R, and Rare each independently selected from a hydrogen atom, hydrocarbon groups, and phos 50 phorus-containing groups of formula (11), wherein said hydrocarbon groups are optionally and independently Substituted with one or more heteroatoms or heteroatom wherein R is selected from a hydrogen atom, hydrocar groups. 55 bon groups, and phosphorus-containing groups of for 33. The ionic liquid of claim 30, wherein BH has a com mula (11), wherein said hydrocarbon groups are option position according to the chemical formula: ally and independently substituted with one or more heteroatoms or heteroatom groups. (17) 37. The ionic liquid of claim 30, wherein one or both of the R51 60 amino groups - NR'R'' and - NRR are independently selected from imino groups of formula (1a) and/or phosp C1. N1 R52. Hit haZeno groups of formulas (1b). N r 38. The ionic liquid of claim 34, wherein both of the amino R53 65 groups - NR'R'' and - NR'R'' are independently selected from imino groups of formula (1a) such that BH has a composition according to the chemical formula: US 8,524,388 B2 41 42

(19) (20) R 16 O O

7 es O O wherein m and n are independently 0 or an integer of 1 or S={R19 above, and p is 0 or 1, provided that when p is 0, the 10 group —N—SO (CF), CF. Subtended by p is wherein R. R. R', and R'' are each independently replaced with an oxide atom connected to the sulfur Selected from a hydrogen atom, hydrocarbon groups, atom, and when p is 1, the shown perfluoroalkyl groups amino groups of formula (1), imino groups of formula can optionally crosslink to form a cyclic anion. (1a), and phosphazeno groups of formula (1b), and R' 15 43. The ionic liquid of claim 42, wherein A has a compo is selected from a hydrogen atom hydrocarbon groups, sition according to the chemical formula: wherein said hydrocarbon groups are optionally and independently substituted with one or more heteroatoms or heteroatom groups; and optionally, two or more of (21) R', R'7, R', R', and Rare interconnected. O O 39. The ionic liquid of claim38, wherein at least one of R', | R''. R', and R' is selected from said amino groups. | 40. The ionic liquid of claim 39, wherein all of R', R'7, O O R', and R'' are selected from said amino groups, such that BH has a composition according to the chemical formula: 25 wherein m and n are independently 0 or an integer of 1 or above. 44. The ionic liquid of claim 42, wherein A has a compo (19a) sition according to the chemical formula:

30 (23) O | | 35 O

wherein R,R,R, R57, R,R,R,R, and R2 are wherein m is 0 or an integer of at least 1. each independently selected from a hydrogen atom and 45. An ionic liquid-containing film useful as a proton hydrocarbon groups, wherein said hydrocarbon groups exchange membrane for a fuel cell, the ionic liquid-contain are optionally and independently substituted with one or 40 ing film comprising the ionic liquid of claim 1. more heteroatoms or heteroatom groups; 46. An ionic liquid-containing film useful as a proton optionally, the amino groups - NRR, NR7R, exchange membrane for a fuel cell, the ionic liquid-contain NR'R'', and NR'R' of formula are selected ing film comprising the ionic liquid of claim 2. from imino groups according to formula (1a) and/or phosphaZeno groups according to formula (1b); and 45 47. An ionic liquid-containing film useful as a proton optionally, two or more of R,R,R,R,R,R,R, exchange membrane for a fuel cell, the ionic liquid-contain and Rare interconnected. ing film comprising the ionic liquid of claim 30. 41. The ionic liquid of claim 1, wherein A is a conjugate 48. An ionic liquid-containing film useful as a proton base of a superacid HA. exchange membrane for a fuel cell, the ionic liquid-contain 42. The ionic liquid of claim 41, wherein A has a compo 50 ing film comprising the ionic liquid of claim 41. sition according to the chemical formula: k k k k k