Synthesis and characterization of manganese (II) complexes with polybenzimidazo based ligand

Abstract

A series of manganese (II) complexes with the formula [Mn₂LX₄].nH₂O have been synthesized utilizing an exogenous anionic ligand, X =Cl^-, SCN^-, OAc^- or PhCOO^- and the octadentate dinucleating ligand ethylene glycol-his (b-ammino ethyl ether) N,N,N',N'-tetrakis [2-benzimidazolyl]. These complexes have been characterized by elemental analysis, UV, IR and ESR spectra. Cyclic voltammetric studies ofthe complexes reveal that EII2 for the Mn(II) - Mn(II) I Mn(III) - Mn(lI) couple shifts to most positive value with SCN' as anionic ligand, implying that this anion stabilizes the manganese in +2 oxidation state.