Reigoselective Arylation of Thiazole Derivatives at 5-Position via Pd Catalysis under Ligand-Free Conditions

An efficient regioselective arylation of thiazole derivatives via Pd-catalyzed C–H activation is reported. The transformation was hypothesized through a Pd(0/II) catalytic cycle in the absence of special ligand sets. This method provided an efficient process to direct arylation of thiazoles at the 5-position.