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Wo 2009/082437 A9
(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) CORRECTED VERSION (19) World Intellectual Property Organization International Bureau (10) International Publication Number (43) International Publication Date 2 July 2009 (02.07.2009) WO 2009/082437 A9 (51) International Patent Classification: KZ, LA, LC, LK, LR, LS, LT, LU, LY, MA, MD, ME, C07D 207/08 (2006.01) A61K 31/402 (2006.01) MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, C07D 207/09 (2006.01) A61P 5/26 (2006.01) NZ, OM, PG, PH, PL, PT, RO, RS, RU, SC, SD, SE, SG, C07D 498/04 (2006.01) SK, SL, SM, ST, SV, SY, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. (21) International Application Number: PCT/US2008/013657 (84) Designated States (unless otherwise indicated, for every kind of regional protection available): ARIPO (BW, GH, (22) International Filing Date: G M M N S D S L s z τ z U G Z M 12 December 2008 (12.12.2008) z w Eurasian (A M B γ KG> M D RU> τ (25) Filing Language: English TM), European (AT, BE, BG, CH, CY, CZ, DE, DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, LV, (26) Publication Language: English M C M T N L N O P L P T R O S E S I s T R OAPI (30) Priority Data: B F ' B J ' C F ' C G ' C I' C M ' G A ' G N ' 0 G W ' M L ' M R ' 61/008,731 2 1 December 2007 (21 .12.2007) US N E ' S N ' T D ' T G ) - (71) Applicant (for all designated States except US): LIG- Declarations under Rule 4.17: AND PHARMACEUTICALS INCORPORATED [US/ — as to applicant's entitlement to apply for and be granted US]; 11085 N. -
The Synthesis of Molecules Containing Quaternary Stereogenic Centers Via the Intramolecular Asymmetric Heck Reaction
The Synthesis of Molecules Containing Quaternary Stereogenic Centers via the Intramolecular Asymmetric Heck Reaction Reported by Eric P. Gillis April 19, 2007 INTRODUCTION The enantioselective synthesis of compounds containing quaternary stereocenters continues to be a challenging endeavor and is a field of intense interest and development.1,,,,2 3 4 5 From the perspective of methods development, the asymmetric synthesis of compounds containing quaternary stereocenters poses a distinct challenge due to the sterically congested environment in which C-C bonds must be formed and stereochemical information must be transferred. Existing asymmetric methods have been applied successfully in desymmetrization processes that transform prochiral quaternary centers into stereodefined quaternary centers. However, for processes in which a quaternary stereocenter is created directly via a C-C bond forming reaction, only a few asymmetric reactions have been fruitful. The diversity in the array of methods that exist for the synthesis of compounds containing quaternary stereocenters is necessitated in part because of the number of distinct quaternary stereocenter architectures that are possible (Scheme 1). The construction of acyclic quaternary stereocenters is particularly challenging due to the number of degrees of freedom associated with these structures. However, promising results for the construction of these stereocenters via allylation,6 allylic alklyation,7 and Michael addition8 have been reported recently. For the synthesis of cyclic quaternary stereocenters a number of methods have been employed successfully including the intramolecular Heck reaction,9 alkylation,10 arylation,11 and Michael addition12. Fused bicyclic quaternary stereocenters are generally accessed via the desymmetrization of a prochiral quaternary center. In this regard, theoretically any SCHEME 1. -
Unusual Ring Opening of Hexamethyl Dewar Benzene in Its Reaction with Triosmium Carbonyl Cluster
Organometallics 2003, 22, 2361-2363 2361 Unusual Ring Opening of Hexamethyl Dewar Benzene in Its Reaction with Triosmium Carbonyl Cluster Wen-Yann Yeh* and Yu-Chiao Liu Department of Chemistry, National Sun Yat-Sen University, Kaohsiung, Taiwan 804 Shie-Ming Peng and Gene-Hsiang Lee Department of Chemistry, National Taiwan University, Taipei, Taiwan 106 Received April 15, 2003 6 Summary: Os3(CO)10(NCMe)2 catalyzes the transforma- HMDB produces the HMB complex [(η -C6Me6)Fe- 11 tion of hexamethyl Dewar benzene (HMDB) to hexameth- (CO)2]2. In rare cases the HMDB moiety has lost its ylbenzene (HMB). This catalytic reaction is in competi- unity, such as in the reaction of RhCl3‚xH2O with 5 tion with ring opening of the HMDB ligand to give (µ- HMDB, causing a ring contraction to give [(η -C5Me5)- 3 12 H)2Os3(CO)9(µ-η -CH(C6Me5)) (1) and (µ-H)Os3(CO)9(µ3- RhCl2]2. However, the coordination chemistry of HMDB 2 t η -C C(C4Me4Et)) (2). with metal clusters has received little attention. We now The coordination chemistry of strained hydrocarbons report that Os3(CO)10(NCMe)2 not only catalyzes the has fascinated chemists striving to understand the conversion of HMDB to HMB but also causes unusual - - details of structure and reactivity.1 In particular, ben- C H and C C bond activations of the HMDB ligand to zene is rich with high-energy strained isomers, such as form unique cluster complexes. Dewar benzene, prismane, and benzvalene, which in- Treatment of Os3(CO)10(NCMe)2 with HMDB (4-fold) terconvert through complex and mysterious rearrange- at -
United States Patent (19) 11) Patent Number: 5,072,065 Sun Et Al
United States Patent (19) 11) Patent Number: 5,072,065 Sun et al. 45 Date of Patent: Dec. 10, 1991 54 NHIBITING POPCORN POLYMER FORMATION WITH ALKYL HALDES FOREIGN PATENT DOCUMENTS 63-223003 9/1988 Japan. (75) inventors: Hsiang-ning Sun, Houston, Tex.; Steven J. Potlock, Baton Rouge, La. OTHER PUBLICATIONS Liu, Plugging-Up of Equipment by Self-Polymeriza (73) Assignee: Exxon Chemical Patents Inc., tion Butadiene Production and its Prevention, China Linden, N.J. Synthetic Rubber Industry, 11(5) 356-360 (1988) & English abstract. 21 Appl. No.: 647,358 Liu et al., Determination of Traces of Diethylhydrox ylamine Inhibitor in c5 Fraction by Gas Chromatogra 22 Fied: Jan. 29, 1991 phy, China Synthetic Rubber Industry, 12(6), 408-410 (1989) & English abstract. (51 Int, C. ........................... C07C 7/20; B08B 9/00 (52) U.S. C. ..................................... 585/2; 134/22.19; Primary Examiner-Curtis R. Davis 585/3,585/950 Attorney, Agent, or Firm-Linda K. Russell (58 Field of Search ............................... 585/3, 2,950; 57 ABSTRACT 34/22.19 Inhibition of popcorn polymer growth by treatment with an alkyl halide. This compound can be admixed (56) References Cited with organic material from which popcorn polymer is U.S. PATENT DOCUMENTS formed, or added to a system for the recovery, use or 4,404,413 9/1983 Heskell ................................ 585/950 storage of such organic material. 4,941,926 7/1990 Nakajima ................................ 585/5 4,956,020 9/1990 Nakajima ................................ 585/5 16 Claims, No Drawings 5,072,065 1. 2 once present in a system. Some of the seeds become NHIBITING POPCORN POLYMER FORMATION attached to the processing and handling equipment, and WITH ALKYL HALDES cannot be readily removed by mechanical means; more over, being insoluble in most common solvents, they are CONCURRENTLY FILED APPLICATIONS virtually impossible to wash out by use of such solvents. -
Photoacoustic Measurements of Porphyrin Triplet-State Quantum Yields and Singlet-Oxygen Efficiencies
FULL PAPER Photoacoustic Measurements of Porphyrin Triplet-State Quantum Yields and Singlet-Oxygen Efficiencies Marta Pineiro, Ana L. Carvalho, Mariette M. Pereira, A. M. dA. Rocha Gonsalves, Luís G. Arnaut,* and SebastiaÄo J. Formosinho Abstract: Photoacoustic calorimetry was used to measure the quantum yields of singlet molecular oxygen production by the triplet states of tetraphenylporphyrin (TPP), ZnTPP and CuTPP in toluene, yielding values of 0.67 Æ 0.14, 0.68 Æ 0.19 Keywords: metalloporphyrins ´ and 0.03 Æ 0.01, respectively. We show that a novel dichlorophenyl derivative of photoacoustic calorimetry ´ por- ZnTPP is capable of singlet-oxygen production with a 0.90 Æ 0.07 quantum yield. phyrinoids ´ singlet oxygen ´ sensi- The synthesis and characterisation of a new photostable chlorin with high absorptivity tizers in the red that is capable of singlet-oxygen production with 0.54 Æ 0.06 quantum yield is described. Our results suggest that chlorinated chlorins may be interesting new sensitisers for photodynamic therapy. Introduction Type II photooxygenation process in cells.[7, 8] Adequate sensitisers have specific biological and photochemical proper- The ubiquitous tetrapyrrolic macrocycles play highly diverse ties. The desired biological features of the sensitiser are: roles in biological systems.[1±5] The natural roles of these 1) little or no dark toxicity structures stimulated the search for new applications, exploit- 2) selective accumulation and prolonged retention in tumour ing in particular the use of new synthetic porphyrins.[6] One of tissues the more recent and promising applications of porphyrin 3) controlled photofading to reduce the unwanted skin chemistry in medicine is in the detection and cure of photosensitivity side effects and increase light penetration tumours,[7, 8] referred to as photodynamic therapy (PDT). -
Electronic Spectroscopy of Free Base Porphyrins and Metalloporphyrins
Absorption and Fluorescence Spectroscopy of Tetraphenylporphyrin§ and Metallo-Tetraphenylporphyrin Introduction The word porphyrin is derived from the Greek porphura meaning purple, and all porphyrins are intensely coloured1. Porphyrins comprise an important class of molecules that serve nature in a variety of ways. The Metalloporphyrin ring is found in a variety of important biological system where it is the active component of the system or in some ways intimately connected with the activity of the system. Many of these porphyrins synthesized are the basic structure of biological porphyrins which are the active sites of numerous proteins, whose functions range from oxygen transfer and storage (hemoglobin and myoglobin) to electron transfer (cytochrome c, cytochrome oxidase) to energy conversion (chlorophyll). They also have been proven to be efficient sensitizers and catalyst in a number of chemical and photochemical processes especially photodynamic therapy (PDT). The diversity of their functions is due in part to the variety of metals that bind in the “pocket” of the porphyrin ring system (Fig. 1). Figure 1. Metallated Tetraphenylporphyrin Upon metalation the porphyrin ring system deprotonates, forming a dianionic ligand (Fig. 2). The metal ions behave as Lewis acids, accepting lone pairs of electrons ________________________________ § We all need to thank Jay Stephens for synthesizing the H2TPP 2 from the dianionic porphyrin ligand. Unlike most transition metal complexes, their color is due to absorption(s) within the porphyrin ligand involving the excitation of electrons from π to π* porphyrin ring orbitals. Figure 2. Synthesis of Zn(TPP) The electronic absorption spectrum of a typical porphyrin consists of a strong transition to the second excited state (S0 S2) at about 400 nm (the Soret or B band) and a weak transition to the first excited state (S0 S1) at about 550 nm (the Q band). -
Oct. 7, Hydrogen-Transfer Annulations Forming Heterocycles by John
Hydrogen-Transfer Annulations Forming Heterocycles Samuel John Thompson Dong Group – UT Austin Wednesday – October 7th, 2015 Literature Review This review brought to you by Angewandte. 560 ACCOUNT Minireviews A. Nandakumar,E.Balaraman et al. Cp*Ir Complex-Catalyzed Hydrogen Transfer Reactions Directed toward International Edition:DOI:10.1002/anie.201503247 Synthetic Methods German Edition:DOI:10.1002/ange.201503247 Environmentally Benign Organic Synthesis Cp*IrKen-ichi Complex-Catalyzed Hydrogen Transfer Reactions Fujita, Ryohei Yamaguchi* Transition-Metal-Catalyzed Hydrogen-Transfer Graduate School of Human and Environmental Studies, Kyoto University, Kyoto 606-8501, Japan Fax +81(75)7536634; E-mail: [email protected]; E-mail: [email protected] Annulations:Access to Heterocyclic Scaffolds Received 1 October 2004 Avanashiappan Nandakumar,* Siba Prasad Midya, Vinod Gokulkrishna Landge, and Ekambaram Balaraman* The stability of organoiridium complexes was advanta- Abstract: Catalytic activity of Cp*Ir complexes toward hydrogen geous for the studies on stoichiometric reactions in detail; annulations ·heterocycles ·hydrogen transfer · transfer reactions are discussed. Three different types of reactions thus the oxidative addition reaction, which is one of the synthetic methods ·transition metal catalysis have been developed. The first is Oppenauer-type oxidation of alco- hols. This reaction proceeds under quite mild conditions (room tem- most fundamental and important process in organo- perature in acetone) catalyzed by [Cp*IrCl2]2/K2CO3, and both metallic chemistry, has been studied using Vaska’s com- primary and secondary alcohols can be used as substrates. Introduc- 2 he ability of hydrogen-transfer transition-metal catalysts,whichen- plex IrCl(CO)(PPh3)2. -
Hidden Nature, the Startling Insights of Viktor Schauberger
Contents Foreword by David Bellamy 11 Introduction 13 Part One: An Alternative Worldview 1. Schauberger's Vision 25 The water wizard 26; Log flumes 29; Water, source of life 31; Motion is crucial 32; Temperature controls 34; Evolution 34; Balance 35; Implosion 35; The visionary 36. 2. Different Kinds of Energy 39 Subtle energies 39; Schauberger's worldview 39; Why the mystery? 40; Degrees of energy 41; The vortex as the key to creative evolution 42; Energies as creative process 43; Spiritual science 44; Different dimensions 45; Changing octaves 47. 3. The Attraction and Repulsion of Opposites 49 The Sun as a fertilizing entity 49; Polarities 51; Opposites working towards balance 52; Gravity and levity 53. 4. Nature's Patterns and Shapes 55 Sound as resonance 55; Resonance is about qualities 58; Plants have perception and memory 59; Cymatics 60; Patterns and shapes 61; Patterns in motion 62; Rhythms within the solar system 62; The confrontation of two geometric systems 63; Sacred geometry 64; The golden mean 66; The magic of the egg form 67. Part Two: How the World Works 5. Energy Production 73 The inefficiency of modern technology 73; Entropy and ectropy 74; Scientific 'laws' 74; Energy pollution 75; The choice before us 77; Energy defines quality 79; The creative energy vortex 80. 6. Motion — the Key to Balance 85 We use the wrong form of motion 85; The 'original' motion 87; Types of motion 89. 7. The Atmosphere and Electricity 93 Earth's atmosphere 94; Electricity 96; The terrestrial biocondenser 97; Earth as an accumulator of energy 99; Electricism and magnetism 100; Storms, water vapour and climate 101. -
Bond Distances and Bond Orders in Binuclear Metal Complexes of the First Row Transition Metals Titanium Through Zinc
Metal-Metal (MM) Bond Distances and Bond Orders in Binuclear Metal Complexes of the First Row Transition Metals Titanium Through Zinc Richard H. Duncan Lyngdoh*,a, Henry F. Schaefer III*,b and R. Bruce King*,b a Department of Chemistry, North-Eastern Hill University, Shillong 793022, India B Centre for Computational Quantum Chemistry, University of Georgia, Athens GA 30602 ABSTRACT: This survey of metal-metal (MM) bond distances in binuclear complexes of the first row 3d-block elements reviews experimental and computational research on a wide range of such systems. The metals surveyed are titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, and zinc, representing the only comprehensive presentation of such results to date. Factors impacting MM bond lengths that are discussed here include (a) n+ the formal MM bond order, (b) size of the metal ion present in the bimetallic core (M2) , (c) the metal oxidation state, (d) effects of ligand basicity, coordination mode and number, and (e) steric effects of bulky ligands. Correlations between experimental and computational findings are examined wherever possible, often yielding good agreement for MM bond lengths. The formal bond order provides a key basis for assessing experimental and computationally derived MM bond lengths. The effects of change in the metal upon MM bond length ranges in binuclear complexes suggest trends for single, double, triple, and quadruple MM bonds which are related to the available information on metal atomic radii. It emerges that while specific factors for a limited range of complexes are found to have their expected impact in many cases, the assessment of the net effect of these factors is challenging. -
Deep Lights Lesson Plan
Bioluminescence 2009: ocean Living Light on the Deep Sea Floor Expedition Deep Lights www.oceanexplorer.noaa.gov Focus Light-producing processes and organisms in deep-sea environments Grade Level 7-8 (Life Science/Physical Science) Focus Question Image credit: NOAA. How do deep-sea organisms produce light in deep ocean environments? Learning Objectives ] Students will be able to compare and contrast chemiluminescence, bioluminescence, fluorescence, phosphorescence, and triboluminescence. ] Given observations on materials that emit light under certain Image credit: NOAA. conditions, students will be able to infer whether the light- producing process is chemiluminescence, fluorescence, phosphorescence, or triboluminescence. ] Students will be able to explain three ways in which the ability to produce light may be useful to deep-sea organisms. Materials @ Ultraviolet lamp (see Extensions) Image credit: NOAA. @ Materials for demonstrating fluorescence, phosphorescence, chemiluminescence, and triboluminescence; see “Learning Procedure” Step 1b and “Extensions” for a partial list of suppliers @ Watch glasses, petri dishes, bottle caps, or similar containers to hold small samples of solid materials @ Clear glass 50 ml beakers, graduated cylinders, or similar containers for liquid materials @ Plastic sandwich bags, two for each student group @ Pliers; one for each student group, or groups may share Image credit: NOAA. @ One or more large cardboard cartons to provide a darkened space for viewing materials under ultraviolet light, if the classroom -
Contents Contents
Contents CHEMISTRY International January-March 2019 Volume 41 No. 1 Introduction The International Year of the Periodic Table 2019 2 by Jan Reedijk and Natalia Tarasova Features IUPAC and the Periodic Table by G.J. Leigh 6 Criteria for New Element Discovery: Providing Assurance 10 in a Field of Allure and Romance by Sigurd Hofmann Looking Backwards and Forwards at the Development 16 of the Periodic Table by Eric Scerri Isotopic Abundances and Atomic Weights: History of IUPAC 21 Commission II.1 in the Service of Chemistry by John R. De Laeter IUPAC Commission II.1 Today by Juris Meija 24 Isotopes Matter by Norman E. Holden, Tyler B. Coplen, and Peter Mahaffy 27 The New SI: The International System of Units is Getting 32 a Makeover by Ian Mills and Roberto Marquardt IUPAC Wire Election of IUPAC Officers and Bureau Members 36 Juris Meija Made the Top 40 Under 40 37 C. Oliver Kappe is Awarded the 2018 IUPAC-ThalesNano Prize 37 for Flow Chemistry OPCW to Further Enhance Contributions to United Nations’ 38 Sustainable Development Goals 1001 Inventions: Journeys from Alchemy to Chemistry 38 Stamps International 39 Project Place Critical evaluation of homogeneous equilibrium and solubility 40 constants of gadolinium in environmental and biological- relevant conditions 23rd UNESCO/IUPAC Postgraduate Course in Polymer Science 40 Guidance for the Compilation, Critical Evaluation and 40 Dissemination of Chemical Data Making an imPACt On the Discovery of New Elements (IUPAC/IUPAP 42 Provisional Report) IUPAC Periodic Table of the Elements and Isotopes -
Diphosphine Complexes on Alpo4-Sepiolite Supports
catalysts Article Hydrogenation of α,β-Unsaturated Carbonyl Compounds over Covalently Heterogenized Ru(II) Diphosphine Complexes on AlPO4-Sepiolite Supports Verónica Caballero 1, Rafael Estevez 1, Diego Luna 1,* , Felipa M. Bautista 1 , Antonio A. Romero 1 , Laura Aguado-Deblas 1 , Jesús Hidalgo-Carrillo 1 and Isabel Romero 2 1 Departamento de Química Orgánica, Campus de Rabanales, Universidad de Córdoba, Ed. Marie Curie, 14014 Córdoba, Spain; [email protected] (V.C.); [email protected] (R.E.); [email protected] (F.M.B.); [email protected] (A.A.R.); [email protected] (L.A.-D.); [email protected] (J.H.-C.) 2 Departament de Química and Serveis Tècnics de Recerca, Universitat de Girona, C/M. Aurèlia Campmany, 69, E-17003 Girona, Spain; [email protected] * Correspondence: [email protected]; Tel.: +34-957212065 Abstract: In this work, the covalent immobilization of two ruthenium(II) complexes, II II i.e., [Ru Cl (bpea){(S)(-)(BINAP)}](BF4), 1, and [Ru Cl(bpea)(DPPE)](BF4), 2, where BINAP = 2,2’- bis(diphenylphosphino)-1,1’-binaphthyl and DPPE = 1,2-bis(diphenylphosphino)ethane, have been obtained (AlPO4-Sepiolite@1 and AlPO4-Sepiolite@2) by using a N-tridentate ligand N,N-bis-(2- pyridylmethyl)ethylamine (bpea), linked to an amorphous AlPO4-Sepiolite (20/80) inorganic support. Citation: Caballero, V.; Estevez, R.; This AlPO4-sepiolite support is able to immobilize the double amount of ruthenium complex (1.65%) Luna, D.; Bautista, F.M.; Romero, than the amorphous AlPO4 (0.89%). Both heterogenized complexes have been assessed as catalysts A.A.; Aguado-Deblas, L.; in the liquid phase hydrogenation of several substrates with carbonyl and/or olefinic double bonds Hidalgo-Carrillo, J.; Romero, I.