Synthesis, spectral and electrochemical studies of novel porphyrin bound tetranuclear acyclic manganese(III) and copper(II) complexes

Abstract

The tetranucleating manganese(III) and copper(II) complexes of the type Mn₄LP₂, Cu₄LP₂, where H₆LP₂= 1,4 bis[2'-hydroxy-3'-(iminotetraphenylporphyrin)-5'-methylbenzyl] piperazine, were synthesized and characterized. Mn₄LP₂ complex is EPR silent and this indicates that manganese is in +3 oxidation state. Cu₄LP₂ complex shows broad band with <i>g </i>value centered at 2.06 indicates antiferromagnetic coupling. Cyclic voltammetry studies indicating that the Mn₄LP₂ complex undergoes quasireversible electron transfer in the cathodic potential region and irreversible electron transfer in the anodic potential region. Cu₄LP₂ complex undergoes irreversible electron transfer in the cathodic potential region, quasireversible electron transfer in the anodic potential region.