POSNER G. H.; WEITZBERG M.; HAMILL T. G.; ASIRVATHAM E.; CUN-HENG HE; CLA+, TETRAHEDRON, 42,(1986) N 11, 2919-2929
作者:POSNER G. H.、 WEITZBERG M.、 HAMILL T. G.、 ASIRVATHAM E.、 CUN-HENG HE、 CLA+
DOI:——
日期:——
Asymmetric michael additions of ester enolates to enantiomerically pure vinylic sulfoxides
作者:Gary H. Posner、Moshe Weitzberg、Terence G. Hamill、Edward Asirvatham、He Cun-heng、Jon Clardy
DOI:10.1016/s0040-4020(01)90581-2
日期:1986.1
donors to enantiomerically pure Michael acceptor cycloalkenone sulfoxides 1a and 1b and unsaturated lactone sulfoxides 3a and 3b. The level of asymmetric induction in some cases is extraordinarily high (95% e.e. of final 1,5-dicarbonyl products). Adduct ester lactones 5 and 6 can be converted easily into some synthetically versatile, trifunctional, 3-substituted glutarate esters of highenantiomeric purity
1,3-Dipolar Cycloadditions of Diazoalkanes to Activated Sulfoxides: Influence of Lewis Acids
作者:José L. García Ruano、M. Teresa Peromingo、Marina Alonso、Alberto Fraile、M. Rosario Martín、Amelia Tito
DOI:10.1021/jo051574v
日期:2005.10.1
The reactions of diazomethane and diazoethane with (S)-3-p-tolylsulfinylfuran-2(5H)-one (3) and its 4-methyl derivative (4) have been studied. The sulfinyl group was able to completely control the π-facial selectivity of all these reactions, which decreased when the polarity of the solvent increased and could be inverted in the presence of Lewis acids, Yb(OTf)3 being the most efficient catalyst. This