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Trisubstituted Alkenes (Trisubstitut + alkene)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Arylethyne Bromoboration,Negishi Coupling Route to E - or Z -Aryl-Substituted Trisubstituted Alkenes of ,98% Isomeric Purity.

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2010
New Horizon in the Highly Selective Synthesis of Trisubstituted Alkenes
Abstract The hitherto unprecedented palladium-catalyzed cross-coupling of (Z)-,-bromo-,-arylethenylboranes can be made to proceed satisfactorily through (1) the use of highly catalytically active bis(tri- tert -butylphosphine)palladium or dichloro[N,N -bis-(2,6-diisopropylphenyl)imidazol-2-yl](m -chloropyridine)palladium and (2) conversion of the dibromoboryl group to the (pinacol)boryl group. Thus, a wide variety of carbon groups can be used to substitute bromine in ,98% stereo- and regioselectivity, while suppressing the otherwise dominant ,-debromoboration. Together with the alkylethyne-based protocols, the alkyne bromoboration,Negishi coupling tandem process has emerged as the most widely applicable and highly selective route to trisubstituted alkenes including those that are otherwise difficult to access. [source]

Access to Stereodefined Trisubstituted Alkenes via Rhodium-Catalyzed 1,4-Addition of Potassium Trifluoro(organo)- borates to Baylis,Hillman Adducts

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 3 2006
Laure Navarre
Abstract In the presence of a rhodium catalyst, unactivated Baylis,Hillman adducts reacted regioselectively with potassium trifluoro(organo)borates to afford stereodefined trisubstituted alkenes with good yields. This highly efficient reaction (aerobic conditions, low temperature, absence of added phosphane ligand) is believed to proceed via a 1,4-addition/,-hydroxy elimination mechanism. [source]

ChemInform Abstract: Amide-Directed Catalytic Asymmetric Hydroboration of Trisubstituted Alkenes.

CHEMINFORM, Issue 29 2010
Sean M. Smith
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]

ChemInform Abstract: Remarkable Access to Fluoroalkylated Trisubstituted Alkenes via Highly Stereoselective Cobalt-Catalyzed Hydrosilylation Reaction of Fluoroalkylated Alkynes.

CHEMINFORM, Issue 30 2009
Tsutomu Konno
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: Conversion of Allylic Alcohols to Stereodefined Trisubstituted Alkenes: A Complementary Process to the Claisen Rearrangement.

CHEMINFORM, Issue 20 2009
Justin K. Belardi
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: Palladium-Catalyzed cis- and trans-Silaboration of Terminal Alkynes: Complementary Access to Stereo-Defined Trisubstituted Alkenes.

CHEMINFORM, Issue 29 2008
Toshimichi Ohmura
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]

A Synthesis of Trisubstituted Alkenes by a Ru-Catalyzed Addition.

CHEMINFORM, Issue 41 2002
Barry M. Trost
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Rhodium-Catalyzed Formation of Stereocontrolled Trisubstituted Alkenes from Baylis,Hillman Adducts

CHEMISTRY - A EUROPEAN JOURNAL, Issue 18 2009
Thomas Gendrineau
Abstract Efficient and general conditions for the formation of stereodefined trisubstituted alkenes by using the rhodium-catalyzed reaction of unactivated Baylis,Hillman adducts with either organoboronic acids or potassium trifluoro(organo)borates are reported (see scheme). We report here efficient and general conditions for the formation of stereodefined trisubstituted alkenes using the rhodium-catalyzed reaction of unactivated Baylis,Hillman adducts with either organoboronic acids and potassium trifluoro(organo)borates. The use of the [{Rh(cod)OH}2] precursor gave very fast coupling reactions under low catalyst loading, very mild reaction conditions (from room temperature up to 50,°C) and without the need of additional phosphane ligands. Based on the new reaction conditions, the reaction, originally limited to Baylis,Hillman adducts derived from esters, could be extended to a large variety of Baylis,Hillman adducts, bearing either keto, cyano or amido functionalities. Moreover, the reaction of Baylis,Hillman adducts bearing esters functionality was improved and could be conducted at lower temperature using lower catalyst loading. [source]