Catalytic C-H arylation of unactivated heteroaromatics with aryl halides by cobalt porphyrin

Direct C-H arylation of unactivated heteroaromatics with aryl halides catalyzed by cobalt porphyrin is reported. The reaction is proposed to go through a homolytic aromatic substitution reaction. The aryl radical is electrophilic and a SOMO-HOMO interaction is predominant in the aryl radical addition process.