Polynuclear Metal Complexes: Transition Metal Complexes of bis(3-Formyl-Salicylic Acid)-hydrazone

Abstract

Two series of POlynuclear metal complexes of the type (M₂ (3fsa-Hy)₂.nH₂O] and [M₄ (3fsa-Hy)₂, nH₂O], where 3fsa-Hy is an hexadentate Schiff base, derived from 3-formyl salicyclic acid and hydrazine hydrate; M = copper(II), nickel(II), cobalt(II) and vanadyl(II); n = 0,2 or 4 have been isolated. These have been characterised on the basis of elemental analysis, spectral studies, magnetic and conductivity measurements and thermal analvses. In case of binuclear complexes tne metal ions are attached to the “inner” coordination sDhere havinq N₂O₂ ⁻ chromochore. They have planar tetrhedral geometry around them with a slightly lower magnetic moment values at room temperature, while in case of tetranuclear complexes the “inner” coordination sphere and “outer” coordination sohere have N₂O₂ and O₄ ⁻ Chrophores respectively. They show strong anti-ferromagnetic irteraction due to the presence of an oxo-bridge. Both bi- and tetranu-clear complexes are non-electrolvtes in dioxane as evidenced from their low molar conductance values. IR and thermal analyses data of the tetranuclear complexes suggest the presence of coordinated water molecules.