Regioselective Isomerization of 2,3-Disubstituted Epoxides to Ketones: An Alternative to the Wacker Oxidation of Internal Alkenes
作者:Jessica R. Lamb、Michael Mulzer、Anne M. LaPointe、Geoffrey W. Coates
DOI:10.1021/jacs.5b10419
日期:2015.12.2
trans-alkenes followed by a mild and highly regioselective isomerization to give the major ketone isomers in 66-98% yield. Preliminary kinetics and isotopelabeling studies suggest epoxide ring opening as the turnover limiting step in our proposedmechanism. A similar catalytic system was applied to the kinetic resolution of select trans-epoxides to give synthetically useful selectivity factors of 17-23
Dialkylation of gem-dibromocyclopropanes with trialkylmanganate and manganese(II) chloride-catalyzed reaction with alkylmagnesium bromide
作者:Rie Inoue、Hiroshi Shinokubo、Koichiro Oshima
DOI:10.1016/0040-4039(96)01082-9
日期:1996.7
gem-dibromocyclopropanes with trialkylmanganate, derived from manganese(II) chloride and three equivalents of Grignard reagent or alkyllithium, followed by an addition of electrophiles provided dialkylated cyclopropanes in good yields. It was found the reaction with alkylmagnesium halide proceeded in the presence of a catalytic amount of manganese(II) chloride.