Synthesis and Characterization of Some Cobalt(II), Copper(II), and Nickel(II) Complexes with New Schiff Bases from the Reaction ofp‐Aminoazobenzene with Salicylaldehyde

Two new Schiff bases have been synthesized by the reaction of p‐aminoazobenzene with salicylaldehyde (L1H) and the oxidative polycondensation product of L1H (L2H2). The complexes of cobalt(II), copper(II), and nickel(II) with L1H and L2H2 have been prepared. The ligands and their complexes have been characterized by elemental analyses, IR spectra, electronic absorption spectra, mass spectra, 1H and 13C NMR spectra, and magnetic susceptibility measurements. The thermal properties of all complexes have been studied by TG and DTA. The analytical data show that the metal to ligand ratio in the L1H complexes is 1:2, but in the L2H2 complexes it is 1:1.