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Heck Coupling Reaction (heck + coupling_reaction)
Selected AbstractsChemInform Abstract: Catalytic Performance of a Phosphapalladacycle Bearing a Biphenyl Moiety, Possessing an sp3 C,Pd Bond, Toward the Heck Coupling Reaction.CHEMINFORM, Issue 11 2010Shirin Nadri Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Noncatalytic Heck Coupling Reaction Using Supercritical Water.CHEMINFORM, Issue 42 2003Rong Zhang No abstract is available for this article. [source] Fluorapatite-Supported Palladium Catalyst for Suzuki and Heck Coupling Reactions of HaloarenesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7 2007M. Lakshmi Kantam Abstract A fluorapatite-supported palladium catalyst (PdFAP) was synthesized by treatment of fluorapatite (prepared by incorporating the basic species fluoride ion into apatite in situ by co-precipitation) with bis(benzonitrile)palladium(II) chloride in acetone. The catalyst displayed high catalytic activity for Suzuki coupling of aryl iodides and bromides with boronic acids at room temperature and chloroarenes at 130,°C in the presence of tetrabutylammonium bromide to give biaryls in excellent yields. Heck olefination of chloroarenes was also successfully carried out by this catalyst. PdFAP was recovered quantitatively by simple filtration and reused with consistent activity. PdFAP was well characterized by XRD, FTIR, XPS, ICP-AES, CO2 TPD and CHN elemental analysis. [source] Application of N,N-Bis(diphenylphosphino)aniline Palladium(II) Complexes as Precatalysts in Heck Coupling Reactions.CHEMINFORM, Issue 47 2007Bahattin Guemguem Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Synthesis and Catalytic Applications of Self-Assembled Carbon Nanofoams,ADVANCED MATERIALS, Issue 2 2008J. García-Martínez A new surfactant-templated carbon material, carbon nanofoam (CNF), has been synthesized with a semicrystalline and conductive framework, high surface area and interconnected porous structure, and prepared in a wide variety of bulk shapes and forms. CNF was also successfully applied as a support for palladium in the Heck coupling reaction. Pd/CNF catalyst exhibited negligible Pd cluster growth and agglomeration, and retained high activity even after multiple runs. [source] Thiosemicarbazone Salicylaldiminato-Palladium(II)-Catalyzed Mizoroki,Heck ReactionsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2010Guanlei Xie Abstract Four tridentate thiosemicarbazone salicylaldiminato-palladium(II) complexes of the general formula [Pd(saltsc-R)PPh3] [saltsc=salicylaldehyde thiosemicarbazone; R=H (1), 3- tert -butyl (2), 3-methoxy (3), 5-chloro (4)], have been evaluated as catalyst precursors for the Mizoroki,Heck coupling reaction between a variety of electron-rich and electron-poor aryl halides and olefins. The palladium complexes (0.1,1,mol% loading) were found to effectively catalyze these reactions with high yields being obtained when aryl iodides and aryl bromides were utilized. The effects of base, catalyst loading, reaction temperature and reaction time on the catalytic activity of the most active complex were also investigated. [source] Synthesis of deuterium-labelled 6-[5-(4-amidinophenyl)furan-2-yl]nicotinamidine and N -alkoxy-6-{5-[4-(N -alkoxyamidino)phenyl]- furan-2-yl}-nicotinamidinesJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 4 2004Mohamed A. Ismail Abstract 6-[5-(4-Amidinophenyl)furan-2-yl]nicotinamidine- d4 (5) was synthesized from 6-[5-(4-cyanophenyl)furan-2-yl]nicotinonitrile- d4 (3), through the bis - O -acetoxy-amidoxime followed by hydrogenation. Compound 3 was prepared from 6-(furan-2-yl)-nicotinonitrile by a Heck coupling reaction with 4-bromobenzonitrile- d4, a product of selective cyanation reaction of 1,4-dibromobenzene- d4 with Cu(1)CN. Deuterium-labelled N -methoxy-6-{5-[4-(N -methoxy-amidinophenyl]-furan-2-yl}-nicotinamidines were prepared via methylation of their respective amidoximes with dimethyl sulfate- d6 in aqueous sodium hydroxide in good yields. Copyright © 2004 John Wiley & Sons, Ltd. [source] Hyperbranched copolymer containing triphenylamine and divinyl bipyridyl units for fluorescent chemosensorsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 1 2009Jichang Feng Abstract A fluorescent hyperbranched copolymer (HTP) and a linear copolymer (PTP) as a reference sample to HTP both containing triphenylamine and divinyl bipyridyl units were synthesized via Heck coupling reaction from 5,5,-Divinyl-2,2,-bipyridyl with tris(4-bromophenyl)amine and with 4,4,-dibromotriphenylamie, respectively. The chemical structure of HTP was confirmed by FTIR, 1H NMR, and 13C NMR. The polymer HTP had a number-average molecular weight of 1895 and a weight-average molecular weight of 2315, and good solubility in conventional organic solvents, such as THF, DMF, and chloroform, and exhibited good thermal stability. The UV,vis absorption and photoluminescence (PL) spectra exhibited absorption maximum at 428 nm and emissive maximum at 531 nm for the HTP solution. The spectroscopic results of HTP and PTP indicated that hyperbranched conjugated structure increases the effective conjugation length, as compared with corresponding linear conjugated structure. The fluorescence of the polymer in solution can be quenched by various transition metal ions. The effect of backbone structure of the conjugated polymer-based chemosensors on the sensitivity and selectivity in metal ions sensing have been investigated, and the quenching effect of HTP is more sensitive toward transition metal than linear copolymer PTP. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 222,230, 2009 [source] Polymer-supported palladium complexes with C,N-ligands as efficient recoverable catalysts for the Heck reactionAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 9 2010Yu-xia Liu Abstract A series of new polymer-supported palladium complexes with C,N-ligands (1a,e and 2a,c) were easily synthesized. The synthesized catalysts could be applied as efficient heterogeneous catalysts for the Heck coupling reaction (turnover frequency up to 12 600 h,1). Additionally, the catalysts could be recovered by a simple filtration progress and could be reused for at least five times with a slow progressive decrease in activity. Copyright © 2010 John Wiley & Sons, Ltd. [source] Palladium supported on polyether-functionalized mesoporous silica.APPLIED ORGANOMETALLIC CHEMISTRY, Issue 3 2010Synthesis, application as catalyst for Heck coupling reaction Abstract A new catalytic system based on Pd supported on polyether-functionalized mesoporous silica was prepared. This material was obtained by co-hydrolysis and polycondensation of tetraethylorthosilicate and a bis-silylated triblock copolymer P123 (Mw = 5800) followed by the decomposition of Pd(OAc)2 salt. We have shown that this material can be applied as powerful heterogeneous catalyst for the Heck coupling reaction. Copyright © 2009 John Wiley & Sons, Ltd. [source] Benzimidazolin-2-ylidene,palladium-catalysed coupling reactions of aryl halidesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 7 2005Yetkin Gök Abstract The in situ prepared three-component system Pd(OAc)2,1,3-dialkylbenzimidazolium chlorides (2a,f) and Cs2CO3 catalyses, quantitatively, the Suzuki cross-coupling of deactivated aryl chlorides and Heck coupling reactions of aryl bromide and iodide substrates. The 1,3-dialkylbenzimidazolium salts (2a,f) were characterized by conventional spectroscopic methods and elemental analysis. Copyright © 2005 John Wiley & Sons, Ltd. [source] Palladium-Catalyzed Desulfitative Mizoroki,Heck Couplings of Sulfonyl Chlorides with Mono- and Disubstituted Olefins: Rhodium-Catalyzed Desulfitative Heck-Type Reactions under Phosphine- and Base-Free ConditionsCHEMISTRY - A EUROPEAN JOURNAL, Issue 9 2005Srinivas Reddy Dubbaka Abstract New conditions have been found for the desulfitative Mizoroki,Heck arylation and trifluoromethylation of mono- and disubustituted olefins with arenesulfonyl and trifluoromethanesulfonyl chlorides. Thus (E)-1,2-disubstituted alkenes with high stereoselectivity and 1,1,2-disubstituted alkenes with 12:1 to 21:1 E/Z steroselectivity can be obtained. Herrmann's palladacycle at 0.1 mol,% is sufficient to catalyze these reactions, for which electron-rich or electron-poor sulfonyl chlorides and alkenes are suitable. If phosphine- and base-free conditions are required, 1 mol,% [RhCl(C2H4)2] catalyzes the desulfitative cross-coupling reactions. Contrary to results reported for [RuCl2(PPh3)2]-catalyzed coupling reactions with sulfonyl chlorides, the palladium and rhodium desulfitative Mizoroki,Heck coupling reactions are not inhibited by radical scavenging agents. Possible sulfones arising from the sulfonylation of alkenes at 60,°C are not desulfitated at higher temperatures in the presence of the Pd or Rh catalysts. De nouvelles conditions sont rapporteés pour les couplages désulfitants du type Mizoroki,Heck des chlorures d'arènesulfonyles et trifluorométhanesulfonyle avec des oléfines mono- et disubstitueés. La méthode permet la synthèse de (E)-alcènes 1,2-disubstitués avec haute stéréosélectivité et d'alkènes 1,1,2-trisubstitués avec des stéréosélectivités E/Z variant de 12:1 à 21:1. La palladacycle de Herrmann à 0.1 mol% est suffisant pour catalyser ces reactions qui peuvent engager des chlorures de sulfonyles et des alcènes soit riches ou pauvres en électron. Si des conditions sans phosphine et sans base sont requises, 1 mol,% de [RhCl(C2H4)2] est un excellent catalyseur pour ces couplages désulfitants. Contrairement à ce qui est rapporté pour des réactions analogues catalysées par [RuCl2(PPh3)2] et qui impliquent des intermédiaires radicalaires, les couplages du type Mizoroki,Heck désulfitants catalysés par des complexes de palladium ou de rhodium ne sont pas inhibés par des pièges à radicaux. De plus, les sulfones qui peuvent se former par sulfonylation des alcènes (60,oC) ne sont pas désulfitées à plus haute température en présence des catalyseurs au Pd ou au Rh. [source] Synthesis of (-)-herbertenediol and (aR, aS)-mastigophorenes A via asymmetric intramolecular heck coupling reaction,CHINESE JOURNAL OF CHEMISTRY, Issue 12 2001Ai-Min Zhang Abstract Total enantioselective synthesis of the natural (-)-Herbertenediol (1) was accomplished in eleven steps with an overall yield of 15% starting from the 2-methoxy-4-methyl-phenol. The total synthesis features asymmetric intramolecular Heck reaction and Wolff-Kishner-Huang reduction. (aR, aS)-Mastigophorenes A was also synthesized through the oxidative coupling reaction. [source] | |||||||||||||||||||||||||