Cobalt-catalyzed regioselective synthesis of pyrrolidinone derivatives by reductive coupling of nitriles and acrylamides

A convenient and highly regioselective method is described for the preparation of 5-methylenepyrrolidinone derivatives from various nitriles and acrylamides by a cobalt-catalyzed reductive coupling reaction. A possible mechanism is described that has involved the formation of a cobaltaazacyclopentene intermediate from nitrile and acrylamide, protonation, keto-amide cyclization and dehydration.