Synthesis and Characterization of New Schiff Base Ligand and Its Complexation to Cu(II)

A new bis-Schiff base salophen type Cu(II) complex named as p- bis(3,4-diaminobenzophenimine) phenylenediamine Cu(II) complex, was synthesis via a simple and routine procedure. The desired ligand was prepared through formation of two consecutive imine bond using p-phenylenediamine and 3,4-diaminobenzophenon, followed by reaction with salicylaldehyde and formation of a tetra-dentate ligand. The ligand and its copper complex were characterized step by step with FTIR, 1H NMR, 13C NMR, UV-Vis, CHNS and ICP-OES instruments. Vibrations correspond to two imine (-C=N) bonds were advent at 1604 cm-1 and 1650 cm-1 which the latter one due to complexation to Cu(II) bearing to red shift and was shifted to 1635 cm-1. Chemical shifts at 5.03 ppm, 11.03 ppm and 9.90 ppm in the 1H NMR spectra were related to primary amine, hydroxyl group and imine bond respectively. UV-Vis spectra show well chelation of copper to the ligand so that the absorption bond at 350 nm for imine bond was faded due to chelation. ICP analysis shows stoichiometric chelation for Cu(II) into the ligand.

Keywords:

Bis-tetradentate ligand , Schiff base , p- bis(3 , 4-diaminobenzophenimine) phenylenediamine , Copper complexation , Spectral studies