New copper(II) and vanadium(IV) complexes based on allylamine-derived Schiff base ligand; synthesis, crystal structure, electrochemical properties and DFT calculations

Abstract

Two new Schiff base complexes, CuL2 (1) and [VOL2]n (2), were synthesized from the reaction of CuCl2·2H2O and VO(acac)2 with a bidentate NO-donor Schiff base ligand (HL: 5-bromo-2-((allylimino)methyl)phenol). These two complexes were characterized by elemental analysis, FT-IR, UV–Vis, and X-ray diffraction techniques. The single crystal X-ray analysis of (1) demonstrated a four-coordinated complex by two nitrogen and phenolate atoms. In the complex (2), the coordination environment around the vanadium ion is distorted octahedral. In addition, DFT calculations and electrochemical behavior studies of complexes were done in this work. The nature of the interaction between metal ions and ligands was investigated using DFT calculations employing NBO analyses. The electrochemistry of complexes showed a metal-centered reduction peak corresponding to the CuII/I and VIV/ III at −0.86 V and −1.51 V, respectively.