α‐Angelica Lactone Catalyzed Oxidation of Pyrrolidines to Lactams

Abstract Herein, we report an efficient protocol for the synthesis of γ‐lactams from pyrrolidines and oxygen. The strategy follows a two‐step process involving an initial generation α‐amino alkyl radicals from pyrrolidines and oxygen in presence of 4‐dimethylaminopyridine (DMAP) followed by trapping of the radical with oxygen species. This protocol demonstrates good functional group acceptance and provides a direct method to access γ‐lactams. The lactam derivatives were obtained in up to 98 % yield.