Redox behaviour of the β-dihydroporphycene cobalt complex: study on the effect of hydrogenation of the ligand

The dihydrogenated porphycene cobalt(II) complex was synthesized and electrochemical experiments were carried out. The one-electron reduction of the complex proceeded at the central metal to afford the Co(I) species; in contrast, for the non-hydrogenated porphycene cobalt(II) complex, the one-electron reduction gave the ligand reduced radical anion species. The reactivity of the one-electron reduced species with alkyl halides showed clear differences between the complexes. Hydrogenation of the β-position of the porphycene makes it possible to generate a central cobalt reduced species possessing a higher reactivity than the ligand reduced radical anion species.