Photocatalyst and additive-free visible light induced trifluoromethylation-arylation of N-arylacrylamides with Umemoto's reagent.

A visible light induced highly convenient and practical method for the trifluoromethyl-arylation of N-arylmethacrylamides has been developed using Umemoto's reagent as the trifluoromethyl source. This user-friendly approach can proceed under visible light irradiation without any transition metal, photocatalyst and additive at room temperature. The strategy presented here provides access to trifluoromethylated oxindoles in good to excellent yields with a broad functional group tolerance. Preliminary mechanistic experiments indicated that the reaction process involves a homolytic cleavage of Umemoto's reagent irradiated by visible light.