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Heck Arylation (heck + arylation)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Simple Methodology for Heck Arylation at C-8 of Adenine Nucleosides

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2008
Pallavi Lagisetty
Abstract A simple method for the arylation of 8-vinyladenine nucleoside derivatives is reported. With a broad set of aryl iodides and bromides, the reaction is catalyzed by the simple combination palladium acetate/tris(o -tolyl)phosphine/triethylamine [Pd(OAc)2/(o -tol)3P/Et3N]. As expected, aryl chlorides are more difficult coupling partners but some undergo reactions with more exotic catalysts. Although trans -olefins are the major products, minor amounts of cis -isomers are detected in some cases, and a post -arylation mechanism for their formation is proposed. Finally, by subtle catalyst modulation chemoselective N -arylation of the nucleoside can be achieved in the presence of the vinyl moiety. [source]

ChemInform Abstract: The Scope of the Heck Arylation of Enol Ethers with Arenediazonium Salts: A New Approach to the Synthesis of Flavonoids.

CHEMINFORM, Issue 26 2009
Angelo H. L. Machado
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 of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

ChemInform Abstract: A General Method for Regioselective Heck Arylation of Electron-rich N-Acyl-N-vinylamine with Aryl Halides.

CHEMINFORM, Issue 32 2008
Zhihua Liu
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 of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

Ionic Liquid-Promoted, Highly Regioselective Heck Arylation of Electron-Rich Olefins by Aryl Halides.

CHEMINFORM, Issue 23 2005
Jun Mo
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Mizoroki,Heck Arylation of ,,,-Unsaturated Acids with a Hybrid Fluorous Ether, F-626: Facile Filtrative Separation of Products and Efficient Recycling of a Reaction Medium Containing a Catalyst.

CHEMINFORM, Issue 12 2005
Takahide Fukuyama
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Probing the Stereoselectivity of the Heck Arylation of Endocyclic Enecarbamates with Diazonium Salts.

CHEMINFORM, Issue 24 2003
5R)-Phenylproline Methyl Ester, Concise Syntheses of (2S, Schramm, s C-Azanucleoside.
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

ChemInform Abstract: ,-Regioselective Intermolecular Heck Arylation of N,N-Disubstituted Allylamines.

CHEMINFORM, Issue 16 2001
J. Wu
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]

Chiral Triphenylprolinol Ligands for the Efficient Catalytic Asymmetric Arylation of Aldehydes

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 19 2010
Angélica Venturini Moro
Abstract The synthesis of new chiral amino alcohols by Heck arylation of an enecarbamate is described. These compounds were used as chiral ligands for the catalytic asymmetric arylation of aldehydes and can be easily recovered. Chiral, nonracemic diarylmethanols were obtained in high yields and enantioselectivities. [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 Conditions

CHEMISTRY - A EUROPEAN JOURNAL, Issue 9 2005
Srinivas 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]