Photoredox-Enabled Synthesis of α-Alkylated Alkenylammonium Salts

The development of novel synthetic methods for quaternary ammonium salts is highly demanded since the current synthesis heavily relies on the conventional Menshutkin reaction. Herein, we report photoredox-catalyzed alkylation of α-brominated alkenylammonium salts. Mechanistically, the generation of a highly reactive α-ammoniovinyl radical is the key to our method. This reaction enables the synthesis of various unprecedented α-alkylated alkenylammonium salts.