Rhodium(III)‐Catalyzed, CH Activated Annulation to Form Isocoumarins and α‐Pyrones using the ON Bond as an Internal Oxidant

Abstract A mild, efficient and regioselective CH activation‐based intermolecular redox‐neutral annulation of O ‐benzoylhydroxylamines and internal alkynes has been achieved. The protocol employs an ON bond as the internal oxidant and leads to isocoumarins and α ‐pyrones. magnified image