Directing group assisted rhodium-catalyzed formal C–H arylation and carbonylative arylation of arenes with aryl halides in the presence of CO

A controllable rhodium-catalyzed formal C–H arylation and carbonylative arylation of a variety of readily accessible arenes bearing N-containing heterocycles-directing groups and aryl halides under 1 atm of carbon monoxide (CO) was developed. Good to excellent yields of various bi(hetero)aryls and 7-aroyl indolines were obtained using different substrates. Preliminary mechanistic studies support that a proposed carbonylation/decarbonylation reaction sequence might be involved in the formal C–H arylation. This approach features high efficiency, good functional group tolerance, excellent chemoselectivity, and offers a powerful strategy to access various biaryls, 7-aroyl indolines and 7-aroyl indoles as well.