Regioselective synthesis of multisubstituted isoquinolones and pyridones via Rh(III)-catalyzed annulation reactions.

A mild and efficient Rh(III)-catalyzed regioselective synthesis of isoquinolones and pyridones has been developed. The protocol uses readily available N-methoxybenzamide or N-methoxymethacrylamide and diazo compounds as starting materials. The process involving tandem C-H activation, cyclization, and condensation steps proceeds under mild conditions, and the corresponding isoquinolone and pyridone derivatives were obtained in good to excellent yields with excellent regioselectivities. The process provides a facile approach for the construction of isoquinolone and pyridone derivatives containing various functional groups.