Photoredox-Catalyzed Decarboxylative Elimination via Halogen Atom Transfer

Enamides and enecarbamates offer an excellent balance between stability and reactivity. Decarboxylation of widely available amino acids offers a green and efficient alternative to accessing these reagents. The present study describes a photocatalytic approach for the direct decarboxylative synthesis of enamides via sequential radical decarboxylation and putative halogen-atom transfer (XAT). This operationally simple, economical protocol is scalable and allows for mild reaction conditions and short reaction times. In addition, it obviates the need for transition metals and preactivation of carboxylic acids.