Transition Metal-Free Trifluoromethylation of N-Allylamides with Sodium Trifluoromethanesulfinate: Synthesis of Trifluoromethyl-Containing Oxazolines

A transition metal-free method for the trifluoromethylation of N-allylamides has been developed, and the corresponding trifluoromethyl-containing oxazolines were prepared in moderate to good yields. The protocol uses readily available substituted N-allylamides as the starting materials, inexpensive and easily stored sodium trifluoromethanesulfinate as the trifluoromethyl source, iodobenzene diacetate as the oxidant, and the procedure involves sequential intermolecular trifluoromethylation of alkenes with sodium trifluoromethanesulfinate and intramolecular cyclization. This is the first example to prepare CF3-containing oxazolines. Therefore, the present method should afford an efficient and practical strategy for synthesis of other CF3-containing cyclic compounds.