Preparation and regioselective reactions of novel gem-difluorinated vinyloxiranes with some organometallic reagents

Abstract

Hitherto unknown, relatively labile gem-difluorinated vinyloxiranes were prepared by difluoro-Wittig reactions with α,β-epoxyketones; for these vinyloxiranes alkyl groups were delivered at the fluorine-attached terminal carbon atom in an S_N2′ manner by RLi, while Me₃Al and MeMgBr–CuCl (3∶1) introduced the Me group at the allylic epoxy carbon with retention and inversion of the original stereochemistry, respectively.