Frustrated Lewis Pair Catalyzed C–F Activation of Α-Trifluoromethylstyrenes

A frustrated Lewis pair approach is used for the monoselective C–F activation of α-trifluoromethyl styrenes. Selective C–F activation of α-trifluoromethyl styrenes with trispentafluorophenylborane (BCF) in partnership with tri(ortho-tolyl)phosphine or 2,4,6-triphenylpyridine (TPPy)generates γ-substituted α,α-difluoropropenyl phosphonium or pyridinium salts (respectively). The ability to further functionalize such products at the α and γ-positions is demonstrated through nucleophilic substitutions and metal catalyzed Suzuki couplings to generate a range of difluoromethyl and 1,1-difluoroolefin products.