Visible Light-Promoted Thiobenzoic Acid-Catalyzed Deuteration of Alkylamines and Alkylarenes

A mild and efficient photocatalytic protocol for the α-deuteration of aliphatic amines has been developed using thiobenzoic acid as the HAT catalyst without the extra photocatalyst. This new method is applicable to a variety of aliphatic amines, am-ides, and carbamates with high deuterium incorporations and isolated yields. Alkylated arenes are also amenable to this reac-tion, as the deuteration occurs regio-selectively at the benzylic positions. The deuteration of active pharmaceutical ingredi-ents is also demonstrated. Primary mechanistic studies indicate a HAT pathway for this HIE process.