First examples of enantioselective palladium-catalyzed thiocarbonylation of prochiral 1,3-conjugated dienes with thiols and carbon monoxide: Efficient synthesis of optically active beta,gamma-unsaturated thiol esters

Authors
Citation
Wj. Xiao et H. Alper, First examples of enantioselective palladium-catalyzed thiocarbonylation of prochiral 1,3-conjugated dienes with thiols and carbon monoxide: Efficient synthesis of optically active beta,gamma-unsaturated thiol esters, J ORG CHEM, 66(19), 2001, pp. 6229-6233
Citations number
47
Categorie Soggetti
Chemistry & Analysis","Organic Chemistry/Polymer Science
Journal title
JOURNAL OF ORGANIC CHEMISTRY
ISSN journal
00223263 → ACNP
Volume
66
Issue
19
Year of publication
2001
Pages
6229 - 6233
Database
ISI
SICI code
0022-3263(20010921)66:19<6229:FEOEPT>2.0.ZU;2-Y
Abstract
A catalyst system based on [Pd(OAc)(2)]/(R,R)-DIOP has been found to effect asymmetric thiocarbonylation of certain prochiral 1,3-dienes to produce go od yields of optically enriched,beta,gamma -unsaturated thiol esters. The r eaction was performed under an atmosphere of carbon monoxide (400 psi) at 1 10 degreesC in methylene chloride for 60 h. The asymmetric thiocarbonylatio n proceeded with good to excellent enanotioselectivities (up to 89% ee). Th e stereoselectivity is strongly influenced by the structure of the chiral p hosphine ligands and substrates, as well as by the reaction conditions. The enantiodetermination step is assumed to be CO insertion to a pi -allylpall adium intermediate.