Copper and Zinc Copromoted Bromo(chloro)trifluoromethylation of Alkenes and Alkynes with Trifluoromethanesulfonic Anhydride

The first copper and zinc copromoted trifluoromethylation using trifluoromethanesulfonic anhydride (Tf₂O) as a trifluoromethylating reagent has been developed. The reaction of alkenes or alkynes with Tf₂O in the presence of CuX₂ (X = Br, Cl), Zn powder, and 2,2′-bipyridine affords bromo­(chloro)­trifluoromethylated products in good yields. CuX₂ plays a dual role as the catalyst and halide source, whereas 2,2′-bipyridine acts as both the activation reagent and ligand.