Visible‐Light‐Mediated One‐Pot Synthesis of Fused Bicyclic γ‐Lactams From Cyclic Amino Acids and Acrylates

Abstract

An efficient, economical and modular route for the synthesis of fused bicyclic γ‐lactams has been achieved. Commercially accessible cyclic α‐amino acid derivatives are employed as starting materials and react with acrylates to afford fused bicyclic γ‐lactams, which are a fundamental structural motif, highly prevalent in diverse alkaloids and bioactive compounds, and a promising scaffold for developing novel antimicrobial agents against drug‐resistant microbes. The strategy sequentially proceeds through visible‐light‐induced single‐electron transfer (SET), decarboxylation, radical addition, deprotection, and cyclisation in one pot, applicable to N ‐protected and unprotected cyclic α‐amino acids, internal alkenes, as well as aromatic and aliphatic acrylates, successfully constructing diverse molecular scaffolds of fused bicyclic γ‐lactams comprising four‐, five‐, six‐, and seven‐membered rings. This protocol features broad substrate scope, mild reaction conditions, simple operation and excellent step economy.