Electronic Effects of Ligands on the Cobalt(II)-Porphyrin-Catalyzed Direct C-H Arylation of Benzene

The electronic effects of the porphyrin ligand on the cobalt(II)-porphyrin-catalyzed direct C-H arylation of benzene with 4-iodotoluene were explored. The investigation was facilitated by the easy preparation of various substituted porphyrin ligands. The reaction rates were found to be dependent on the electron richness of the cobalt(II)-porphyrins. Such effects are consistent with the electronic influences on the rate-determining aryl iodide bond cleavage.