Stereocontrolled synthesis of either trans- or cis-trimethylsilylvinyloxiranes via sulfonium ylides
Abstract
trans- or cis-β-Trimethylsilylvinyloxiranes are prepared by the reaction of aldehydes with a 3-trimethylsilylated dimethylsulfonium allylide under phase-transfer conditions or with a preformed 3-trimethylsilylated diphenylsulfonium allylide in the presence of LiBr, both in excellent yields and high stereoselectivity.