A nickel-catalyzed defluorination of α-trifluoromethylated allyl/propargyl carbonates using bis(pinacolato)-diboron (B2pin2) as a reactant is described. The reaction proceeds under relatively mild reaction conditions, providing conjugated gem-difluoroalkenes in moderate to good yields. Applications of the resulting 1,1-difluoro-1,3-dienes by [4 + 2] cycloaddition reactions with maleimide led to cyclic fluorinated products efficiently.

 More Details: https://pubs.acs.org.ccindex.cn/doi/10.1021/acs.orglett.8b03841