Synthesis, characterization and thermal properties of the new Azo-containing salicylidenic schiff bases and their copper (II) complexes

In this paper, six new azo Schiff base ligands (1-6) were synthesized in excellent yields by the condensation reaction of 5-(4-nitrophenylazo) salicylaldehyde with ethylamine, hexylamine, ethanolamine and benzylamine in the presence glacial acetic acid, respectively. After characterizing the newly synthesized ligands with melting point, TLC, IR, H-NMR, UV-Visible, elemental analyses and mass spectral data, they were reacted with copper acetate in 1:2 molar ratio (metal: ligand) to obtain copper (II) complexes (1a-6f). The structures of copper (II) complexes were characterized by IR spectra and elemental analyses. The thermal stability of the azo Schiff base ligands and related complexes were studied by using differential scanning calorimetry (DSC) and thermogravimetric analyses (TGA). (author)