Rhodium-BisbenzodioxanPhos Complex-Catalyzed Homogeneous Enantioselective Pauson-Khand-Type Cyclization in Alcoholic Solvents
作者:Fuk Yee Kwong、Hang Wai Lee、Liqin Qiu、Wai Har Lam、Yue-Ming Li、Hoi Lun Kwong、Albert S. C. Chan
DOI:10.1002/adsc.200505105
日期:2005.11
s was found to be highly effective in the co-operative processeses of aldehyde decarbonylation and cascaded enantioselective Pauson–Khand-type reactions. Various 1,6-enynes were transformed to the corresponding bicyclic cyclopentenones in good yields and enantiomeric excesses (up to 96% ee). The attractive feature of this new Rh-catalyzed homogeneous dual catalysis system is that the reaction can be
作者:Fuk Yee Kwong、Yue Ming Li、Wai Har Lam、Liqin Qiu、Hang Wai Lee、Chi Hung Yeung、Kin Shing Chan、Albert S. C. Chan
DOI:10.1002/chem.200401237
日期:2005.6.20
operationally simple protocol allows both catalyst and reactants to be handled under air without precautions. Various enynes were transformed to the corresponding bicycliccyclopentenones in good yield and enantiomeric excess (up to 95 % ee). A study of the electronic effects of the enyne substrates revealed a correlation between the electronic properties of the substrates and the ee value obtained in
organic molecules are on demand. Here we present two Pd-catalyzed multicomponent reactions that provide functionalized oxazolidinones from propargylamines, aryl halides and CO2 as starting materials. These transformations, devoid of high CO2 pressures, represent a streamlined stereocontrolledsynthesis of previously inaccessible versions of these useful heterocycles in an atom-economic manner, as up to
Compositions and methods for visible-light-controlled ruthenium-catalyzed olefin metathesis
申请人:The Trustees of Columbia University In The City of New York
公开号:US11331656B2
公开(公告)日:2022-05-17
The present disclosure provides compositions and methods for metathesizing a first alkenyl or alkynyl group with a second alkenyl or alkynyl group, the composition comprising a ruthenium metathesis catalyst and a photoredox catalyst that is activated by visible light.
Development of a Titanocene-Catalyzed Enyne Cyclization/Isocyanide Insertion Reaction
作者:Scott C. Berk、Robert B. Grossman、Stephen L. Buchwald
DOI:10.1021/ja00098a020
日期:1994.9
The first early transition metal-catalyzed enyne cyclization reaction is described. The system converts enyne substrates to bicyclic iminocyclopentenes through the use of 10 mol % of Cp(2)Ti(PMe(3))(2) in the presence of a silyl cyanide. Subsequent hydrolysis produces the corresponding bicyclic cyclopentenones in good overall yield. The cyclization reaction is tolerant of polar functional groups such as ethers, amines, and esters and is diastereoselective with certain chiral enyne substrates.