Modular Access to Azepines by Directed Carbonylative C–C Bond Activation of Aminocyclopropanes

A modular Rh-catalyzed entry to azepines is outlined. Under a CO atmosphere, protecting group directed C–C bond activation of aminocyclo­propanes provides rhodacyclo­pentanones. These intermediates are effective for intramolecular C–H metalation of either an N-aryl or N-vinyl unit en route to azepine ring systems. Thus, byproduct-free heterocyclizations are enabled by sequential C–C activation and C–H functionalization steps.