Rh(II)-Catalyzed Site-Selective Insertion of Quinoid Carbene into Quinoline N -Oxides to Synthesize METHOX-Inspired Heterobiaryls

A Rh(II)-catalyzed straightforward and efficient method is developed for the construction of METHOX-inspired heterobiaryls via the C2-naphtholation of quinoline N -oxide using diazonaphthoquinone as a coupling partner. In general, the reaction consists of cross-coupling between two electrophilic centers like the C2 center of quinoline N -oxide and the carbenic carbon of quinoid carbene. The developed method was extended to a scope with broad functionality. Preliminary mechanistic investigations and DFT calculations suggest a plausible reaction mechanism.