Synthesis of Trifluoromethyl-allenes by Gold-Catalyzed Rearrangement of Propargyl Benzyl Ethers

A new method for the synthesis of trifluoromethyl-allenes from easily accessible a-trifluoromethyl-propargyl benzyl ether derivatives following a gold-catalyzed intramolecular hydride transfer has been developed. Various di- and trisubstituted trifluoromethyl-allenes were obtained in good to excellent yields.