C-O Activation by a Rhodium Bis(N-Heterocyclic Carbene) Catalyst: Aryl Carbamates as Arylating Reagents in Directed C-H Arylation.

Despite recent progress in the catalytic transformation of inert phenol derivatives as alternatives to aryl halides and triflates, attempts at the cross-coupling of inert phenol derivatives with the C−H bonds of arenes have met with limited success. Herein, we report the rhodium-catalyzed cross-coupling of aryl carbamates with arenes bearing a convertible directing group. The key to success is the use of an in situ generated rhodium bis(N-heterocyclic carbene) species as the catalyst, which can promote activation of the inert C(sp2)−O bond in aryl carbamates.