Cobalt-catalyzed intramolecular C–N and C–O cross-coupling reactions: synthesis of benzimidazoles and benzoxazoles

Abstract

Cobalt(II)-complex catalyzes efficiently the intramolecular C–N and C–O cross-couplings of Z-N′-(2-halophenyl)-N-phenylamidines and N-(2-bromophenyl)benzamides to afford the corresponding substituted benzimidazoles and benzoxazoles in the presence of K₂CO₃ at moderate temperature. The protocol is general, air stable and affords the products selectively in moderate to high yield.