Synthesis, characterization, and electrochemical study of some novel, azo-containing Schiff bases and their Ni(II) complexes

Abstract

Abstract Five novel azo-azomethine ligands with NN'OS coordination spheres were prepared by reaction of methyl-2-{ N -(2′-aminoethane)}-amino-1-cyclopentenedithiocarboxylate (Hcden) with ( E )-2-hydroxy-5-(phenyldiazenyl)benzaldehyde and its substituted derivatives and then the corresponding nickel(II) complexes were synthesized. The structures of ligands and the complexes were characterized by elemental analyses, IR, UV–Vis, 1 H NMR spectroscopy and cyclic voltammetry. The structures of (methyl 2-(2-(( E )-2-hydroxy-5-(( E )- p -tolyldiazenyl)benzyli deneamino)ethylamino)cyclopent-1-enecarbodithioato)nickel(II) and (methyl 2-(2-(( E )-5-(( E )-(4-chlorophenyl)diazenyl)-2-hydroxybenzylideneamino)ethylamino)cyclopent-1-enecarbodithioato)-nickel(II) have been determined by X-ray crystallography. The X-ray results confirm that the geometry of the complexes are slightly distorted square-planar structures. The nickel(II) ions coordinate to two nitrogen atoms from the imine moiety of the ligand, a sulfur atom from the methyl dithiocarboxylate moiety and a phenolic oxygen atom.