Stereodivergent hydrodefluorination of gem-difluoroalkenes: selective synthesis of (Z)- and (E)-monofluoroalkenes

We have developed a novel approach for the stereodivergent hydro-defluorination of gem-difluoroalkenes using copper(I) catalysts to obtain stereodefined monofluoroalkenes. Both (Z)- and (E)-terminal monofluoroalkenes were obtained by the hydrodefluorination of gem-difluoroalkenes in the presence of copper(I) catalysts and diboron or hydrosilane, respectively, with high stereoselectivity. DFT calculations were conducted to elucidate the stereoselectivity.