Synthesis and characterization of some new Schiff base ligands and their complexes with cobalt(II), nickel(II) and copper(II)

Syntheses of three series of new mononuclear complexes with some new Schiff base ligands have been reported. The new Schiff bases which were used in, these complexes were obtained from the Schiff base condensation of 4-nitroaniline and salicylaldehyde and its derivatives (5-bromo-salicylaldehyde, 5-chlorosalicylaldehyde and 4-methoxysalicyladehyde). The synthesis of these Schiff bases have been performed with acid catalyst and their characterization were explained. In synthesis of these new Shiff bases, we have investigated the effects of different groups on aldehyde and amine in their reactivity in Schiff base condensation reaction was investigated. The study of intramolecular hydrogen bonds is interesting because of the high thermodynamic and structural stability of these systems. The chemical structure of these compounds was confirmed by H-1 NMR and IR spectroscopy. ne spectroscopic studies of these compounds show significant importance of intramolecular hydrogen bond in their structures.