Copper-catalysed controllable hydrodefluorination of trifluoromethylated alkenes

An effective method for the construction of difluoromethylated alkenes through Cu-catalysed controllable hydrodefluorination of trifluoromethylated alkenes is described. This method provides an alternative approach towards diverse difluoromethyl-containing alkenes in good to excellent yields with an E-configuration. Experimental and computational studies reveal that the hydrodefluorination process involves defluorinative borylation to generate gem-difluoroallylic boronates and subsequent hydrodeborylation.