Stereoselective synthesis of 1-bromo-(or 1-chloro-) 1,1-difluoro-2-alkenes

Article abstract of DOI:10.1016/0022-1139(95)03340-8

A highly regio- and stereo-selective method for the introduction of a bromo- (or chloro-) difluoromethylene group into various unsaturated systems is described. The key step is the treatment of 1,1-difluoro-1-alken-3-ols with thionyl bromide (or chloride).