The titanocene(III) chloridemediated opening of silyloxiranes has been examined. Electron transfer from the metal leads to α-silyl radicals with total regiocontrol. The radicals could be trapped by various olefins, and the corresponding adducts were obtained in good yields (Table). Further substitution of the oxirane by alkyl groups proved detrimental to the reactions, but ring opening remained essentially
Reactions of α-epoxysilanes with organocopper reagents. A stereoselective route to alkenes
作者:Denise C. Chauret、J.Michael Chong
DOI:10.1016/s0040-4039(00)79203-3
日期:1993.6
Reactions of α-epoxysilanes with cuprate reagents can be controlled to give β-silyl alcohols as major products. An oxidation, Grignard addition, and elimination sequence then provides alkenes with up to 98% de.