Stephen L. Crooks

An Improved Preparation of Ethyl 2-Oxo-3-Pyrrolidinecarboxylate

Abstract The title 3-substituted pyrrolidinone is a useful building block that has been prepared via base-catalyzed additions of diethyl malonate to 1-benzene-sulfonylaziridine (3 steps, 43% overall yield),1 1-iodo-2-azidoethane with subsequent reduction and cyclization (49% yield for 5 steps from commercially available materials),2 or chloroacetonitrile with a subsequent Raney Ni reduction (15% overall yield).3 We now wish to report a simple two step process that gives good yields of the title compound.