Synthesis, molecular structure, and properties of six-coordinate iron(III) porphyrin, [OEPFe(Pz)2]ClO4

The effect of pyrazine as axial ligand on the formation and coordination of heme analogue has been studied. A new six coordinate and stable iron(III) heme analogue, [OEPFeIII(Pz)2]ClO4, where OEP is octaethylporphyrin and Pz is pyrazine, has been isolated. The compound has been characterized by different spectroscopic methods 1H NMR, UV–Vis, IR as well as elemental analysis. 1H NMR spectroscopy and magnetic moment measurements show that [OEPFeIII(Pz)2]ClO4 is paramagnetic and iron is six coordinate. The structure of [OEPFeIII(Pz)2]ClO4 has been determined by X-ray diffraction analysis. The four Fe–Np, bond distances have average values of 1.985 Å.