Synthesis and characterization of cobalt(II) chelates of N,N'-ethylene bis-salicylaldimine and related quadridentate ligands

156-160Cobalt(II) complexes with a series of as many as sixteen SALEN type of quadridentate ligands derived by condensing substituted carbonyls and different diamines have been synthesized and characterized by IR, 1N NMR, molar conductivity. magnetic susceptibility measurements and electronic spectral data. Subnormal magnetic moment values infer the presence of dimeric structure for the present complexes. However, electronic spectral data suggest a square planar structure in solution. possibly due to the monomeric structure. Infrared spectral data suggest the bonding of ligands through two ortho phenolic oxygen and two azomethine nitrogen atoms. The electrochemical behaviour of these complexes has been studied by cyclic voltammetry. Additional phenolic groups present in these complexes are useful for the facile synthesis of polymer supported cobalt complexes.