Synthesis and characterization of [Cu2(L)2(OCOCH3)(OCH3)]ClO4 {L=2-[(4-methyl-pyridin-2-ylimino)-methyl]-phenol}: EPR and X-ray studies

A dicopper complex of a Schiff's base, 2-[(4-methyl-pyridin-2-ylimino)-methyl]-phenol, with a bridging acetato ligand has been synthesized and characterized by single crystal XRD, EPR, magnetic susceptibility, IR, UV–Vis, CV and elemental analysis. The X-ray analysis indicates that the system belongs to the triclinic space group <f>P1¯</f>. One of the copper atoms in the binuclear complex adopts a square-pyramidal geometry consisting of the tridentate N-salicylidimine dianions, the neutral monodentate pyridine ligand in the basal plane and the solvent molecule in the apical position, while the other copper assumes a square-planar geometry. A seven line pattern observed at half-field in the frozen solution EPR spectrum confirms the interaction between the two copper ions. The cyclic voltametric studies point to a two-step electron transfer indicating the reduction of the two copper ions to copper(I), i.e., Cu(II)Cu(II) <f>↔</f> Cu(II)Cu(I) <f>↔</f> Cu(I)Cu(I). The molar conductance for the complex measured in methanol solvent indicates that the complex is a 1:1 electrolyte. [Copyright &y& Elsevier]