Synthesis and characterization of some heterobimetallic complexes of Cu, Zn and Mn derived from succinoyldihydrazones

Heterobimettalic Cu, Zn and Mn complexes [ZnCu(L-n)(CH3OH)(3)]center dot xCH(3)OH (((HL1)-L-4) (1), H4L2 (2); x = 0, 1); and [MnCu(L-n)(CH3OH)(3)]center dot xCH(3)OH ((H4L1 (3), H4L2 (4), x = 0, 1) (H4L1 = disalicylaldehydesuccionyldihydrazone, H4L2 = bis(2-hydroxy-1-naphthaldehyde)succinoyldihydrazone) have been synthesized using monometallic copper complexes as metalloligand in methanol medium. Complexes have been characterized by means of elemental analysis, molar conductance, UV-Vis, IR spectroscopy, magnetic moment and ESR. The mu(eff) value for the Zn-II-Cu-II complexes fall in the range 1.73-1.5 B.M. while for Mn-II-Cu-II complexes fall in the region 3.24-3.43 B.M. Electronic spectroscopy suggests that the copper centre has a pseudo square pyramidal stereochemistry in all the complexes while the second metal centre has a distorted octahedral stereochemistry. The dihydrazones are present in enol form in the complexes. The electron transfer reactions of the complexes have been investigated by cyclic voltammetry.