Abstract The addition of 1, 2-dibromotetrafluoroethane (1) to various terminal alkynes (2a– 2j) was performed in DMF with a redox system (NH 4) 2 S 2 O 8/HCO 2 Na· 2H 2 O at 40 C. The products (3) were 1: 1 adducts reductively debrominated under the reaction conditions, with the E isomers in predominance, and were obtained in excellent yields (82–93%).
