Synthesis of gem-Difluoroallylboronates via FeCl2-Catalyzed Boration/β-Fluorine Elimination of Trifluoromethyl Alkenes.

The first ferrous chloride catalyzed boration/β-fluorine elimination of trifluoromethyl alkenes is described. Thus, a full range of gem-difluoroallylboronates were obtained in high yield under mild conditions. As an important fluorinated building block, gem-difluoroallylboronate can be readily converted into diverse difluoro-substituted species.