Synthesis and structural determination of new octaethylporphyrin iron(III) complexes containing cyanamide derivatives as axial ligand

The reactions of heme, OEPFeCl] where OEP is the dianion of octaethylporphyrin, with phenylcyanamide (pcyd) ligands have been studied. Four new porphyrin complexes, OEPFe(L)] (L = pcyd (2), 2-Clpcyd (3), 2-Mepcyd (4), 2,4-Me₂pcyd (5)), have been isolated and characterized by spectroscopic methods. ¹H NMR spectroscopy reveals that the species OEPFe(L)] are paramagnetic and iron is five-coordinate. The structure of OEPFe(pcyd)] (2) has been determined by X-ray diffraction analysis. The four Fe-N, bond distances have average values of 2.062 Å. The average displacement of the iron(III) atom from the mean porphinato core is 0.45 Å. Electrochemical of OEPFe(L)] (L = pcyd (2), 2-Clpcyd (3), 2-Mepcyd (4), 2,4-Me₂pcyd (5)) have been studied by cyclic voltammetry.