A High-Yielding General Synthesis of α-Lactams

Abstract A high-yielding general synthesis of α-lactams (aziridinones) is described. An α-haloamide 1 precursor is cyclized by sodium hydride in the presence of 15-crown-5 ether at room temperature, using dichloromethane as the solvent. The by-products, hydrogen gas and sodium halide, are easily removed. The yields for the six known α-lactams (2B-G) chosen for this study are comparable or superior to previously reported yields, yet only short reaction times and a simple work-up is required.