Magnetic and spectroscopic studies on metal complexes of ons donor ligands—I complexes of Schiff bases formed by condensation of 2-hydroxy-1-naphthaldehyde with N-methyl-S-alkyldithiocarbazates

Nickel(II), copper(II), iron(III) and oxovanadyl(IV) complexes of two Schiff base ligands formed by condensation of 2-hydroxy-1-naphthaldehyde with N-methyl-S-alkyldithiocarbazates have been prepared and characterized by elemental analysis and magnetic and spectroscopic measurements. The Schiff bases, HNaph-SR (R = CH3, −CH2C6H5) behave as uninegatively charged tridentate chelating agents. The mono-ligand nickel(II) complexes, having the general formula, [Ni(Naph-SR)X] () are diamagnetic and square-planar. Variable-temperature magnetic susceptibility data coupled with IR and electronic spectra, suggest a square-planar structure for the copper(II) complexes, [Cu(Naph-SR)X′] (). The iron(III) complexes, Fe(Naph-SR)Cl2 display magnetic moments of about 6.0 B.M. at room temperature, which remain virtually constant over the temperature range 296-93°K. Magnetic susceptibility data and IR evidence agree with a sulphur-bridged polymeric structure for the iron(III) complexes. The oxovanadium(IV) complexes having the stoichiometry, VO(Naph-SR)X. nH2O (n = 0, 2) were also isolated. They possess normal magnetic properties in the temperature range 296-93°K.