Synthesis and characterization of a new unsymmetrical potentially pentadentate Schiff base ligand and related complexes with manganese(II), nickel(II), copper(II), zinc(II) and cadmium(II)

Abstract

New unsymmetric thioether Schiff base amine, 2-(2-aminoethylthio)-N-(thiophene-2- ylmethylene)aniline was prepared by reaction of 2-aminothiophenol with N-(2-bromoethyl) phthalimide and then by thiophene-2-carbaldehyde. Then, the phthalimide group converted to the amine by hydrazine hydrate. The new potentially pentadentate N3S2 donor unsymmetrical Schiff base ligand, 2-(2-(pyridine-2-ylmethyleneamino)ethylthio)-N-(thiophene-2-ylmethylene) aniline (L) was prepared via [1 + 1] condensation of pyridine-2-carbaldehyde with this amine. Manganese(II), nickel(II), copper(II), zinc(II) and cadmium(II) complexes of this ligand were prepared by adding metal salts to an ethanolic solution in this ligand. The thioether amine, ligand (L) and unsymmetric Schiff base complexes are characterized by the appropriate spectroscopic methods such as infrared (IR), UV-Vis, 1H nuclear magnetic resonance (NMR), 13C NMR studies, X-ray, microanalysis and mass spectrometry.