Ligand-bridged Polychelates of 4,4-(4,4 ­Biphenylylenebisazo)- disalicylaldehyde phenylhydrazone.

Polymeric ligand-bridged metal chelates of VO(II), Cr(lll), Mn(Il), Co(II), Ni(II), Cu(ll) and Zn(ll) were preparedon interaction of 4,4 -(4,4 -biphenylylenebisazo)-disalicylaldehyde phenylhydrazone with metal salts in N,N-dimethylformamide (DMF). All the polychelates are dark coloured powders, insoluble in water and common organic solvents. They have very poor solubility in DMF. All the polychelates are found to be noncharged chelate polymers from their conductivities in DMF. Their probable structures were determined from reflectance electronic spectral and magnetic measurements in conjunction with infrared spectroscopy. The diffuse reflectance spectra of VO(II), Cr(III), Mn(II), Co(II), Ni(lI) and Cu(lI) polychelates have been analyzed in terms of ligand-field theory. Infrared spectra have been obtained to determine coordination sites of the ligand. The thermal, magnetic and conductivity measurements are discussed in light of the proposed assigned structure. All the polychelates are believed to have an octahedral stereochemistry. The semi-empirical AM1 calculation was also performed on ligand structure.