[Rh(III)(Cp*)]-catalyzed cascade arylation and chlorination of α-diazocarbonyl compounds with arylboronic acids and N-chlorosuccinimide for facile synthesis of α-aryl-α-chloro carbonyl compounds.

A Rh(III)-catalyzed cascade arylation and chlorination of α-diazocarbonyl compounds with arylboronic acids and N-chlorosuccinimide was achieved. The reaction exhibits excellent functional group tolerance on the organoboron and the diazo reagents; the functionalized α-aryl-α-chlorocarbonyl compounds were obtained in up to 86% yields. The cascade reaction should involve migratory carbene insertion of arylrhodium(III) to form some reactive rhodium(III)-diketonate complexes. Its subsequent reaction with N-chlorosuccinmide afforded the α-chlorocarbonyl products.