Stereospecific Synthesis and Acylation of cis 1-Halo 2-Trimethylsilyl Ethylenes

Abstract
Several routes to 1-halo 2-trimethylsilyl ethylenes have been previously proposed 1-6: from ethyn7yltrimethylilane (addition of HBr1,2), ethyltrichlorosilane (addition H by C1, followed by dehydrohalogenation and further methylation of th Si-C1 bonds)3 or by other ways 4,5, especially by reaction of (2-trimethylsilyl) vinyl lithium with dibromoethane6.