Synthesis and Characterization of an Unsymmetrical Tetradentate Schiff Base and Its Co(II), Ni(II), Cu(II) and Zn(II) Complexes

Schiff base compounds synthesized by condensation reaction between ketones or aldehyde moieties and simple amine groups. The resulted imine is capable to coordinate the transition metal ions. These compounds are known as catalysts, biological active sites, etc. [1-3]. In this research an unsymmetrical tetradentate Schiff base of 1- ((1E) -((E) -1- ((1H-pyrrole - 2-yl) methylene amino) naphthalene-8-ylimino) methyl) naphthalene -2-ol (H-pmanmn) ligand and its Co(II), Ni(II), Cu(II) and Zn(II) complexes were synthesized. In these complexes, the Schiff base ligand coordinated via the imine N, amine N and phenolic O atoms. The ligand and complexes were investigated and characterized by FT-IR, UV-Vis, 1HNMR spectroscopic data, magnetic susceptibility and conductivity measurements, thermal and elemental analysis. The Schiff base structure was confirmed by elimination of carbonyl and appearance of imine peaks in FT-IR spectrum. The results show that Co(II) and Ni(II) have five coordination structure, where Cu(II) and Zn(II) complexes form four coordinate structure. The results of conductivity effects exhibit all the complexes are non-electrolytes