Rh(III)-catalyzed C-H activation/cyclization of benzamides and diazo compounds to form isocoumarins and α-pyrones.

Rhodium-catalyzed intermolecular cyclization of benzamides and diazo compounds via C-H activation has been achieved to construct C-C/C-O bonds for the first time. The process provides a facile approach for the construction of isocoumarins and α-pyrones without the need for high temperature or adding oxidants.