Synthesis, characterization and electrochemistry of mono- and dirhodium(I) meso-diaryl dibenzoporphyrin(2.1.2.1) complexes

A series of mono- and dirhodium(I) meso-diaryl dibenzoporphyrin(2.1.2.1) complexes containing p-tolyl, phenyl or pentafluorophenyl meso-substiuents were synthesized and characterized as to their electrochemical and spectroscopic properties in organic solvents and the data compared to that for same series of free base dibenzoporphyrins in their neutral and protonated forms. The redox behavior of the free base, mono- and di-metallic porphyrins was measured by cyclic voltammetry (CV) in methylene chloride or pyridine before and after the addition of acid in the form of TFA and the products of electron transfer are proposed on the basis of the CV data combined with results from thin-layer UV-visible spectroelectrochemistry. X-ray crystal structures of the dirhodium(I) complexes are also reported.