Synthesis of Indole-Fused 1,4-Diazepinones via Photoredox-Catalyzed Cascade Cyclization Reaction

A photoredox-promoted approach for the synthesis of [1,4]diazepino[1,7-a]indol-6(7H)-ones starting from N-indolyl phenylacrylamides and aroyl chlorides as radical source is reported. This method, that involves a cascade radical addition on C-C double bond followed by intramolecular cyclization at indole C2-position, affords two diastereomeric indole-fused 1,4-diazepinones characterized by a N-C(aryl) axial chirality in yields ranging from 51 to 99%.

Automated summary

A photoredox-promoted approach for the synthesis of [1,4]diazepino[1,7-a]indol-6(7H)-ones starting from N-indolyl phenylacrylamides and aroyl chlorides as radical source is reported. This method involves a cascade radical addition on C-C double bond followed by intramolecular cyclization at indole C2-position, resulting in the formation of two diastereomeric indole-fused 1,4-diazepinones characterized by a N-C(aryl) axial chirality, with yields ranging from 51% to 99%.