A versatile difluorovinylation method: Cross-coupling reactions of the 2,2-difluorovinylzinc–TMEDA complex with alkenyl, alkynyl, allyl, and benzyl halides
2-difluorovinylzinc–TMEDA complex was prepared via a deprotonation–transmetallation sequence starting from commercially available 1,1-difluoroethylene. The complex thus formed was successfully applied to transition metal-catalyzed cross-coupling reactions with a wide range of organic halides, which led to the syntheses of 2,2-difluorovinyl compounds. On treatment with the difluorovinylzinc–TMEDA complex in the presence
Synthesis and reactions of 3,3-difluoroallylphosphonates and 3,3-difluoroallyltriphenylphosphonium bromide
作者:Weiming Qiu、Donald J. Burton
DOI:10.1016/s0022-1139(00)80486-8
日期:1993.11
3,3-Difluoroallyltriphenylphosphonium bromide (1) and 3,3-difluoroallylphosphonates, 2, have been prepared by the reaction of CH2=CHCF2Br with phosphites or triphenyiphosphine in good yield. Wittig reaction of 1 with aldehydes gave the corresponding dienes (ArCH = CHCH = CF2) 4; however, Wadsworth-Emmons reaction of 2 with aldehydes failed to produce the dienes.