In this project, a new tri-dentate H 2 Ihqb {5-Iodo-2-hydroxy-N-(quinolin-8-yl)benzamide} has been prepared using tetrabutylammonium bromide (TBAB) as an environmentally friendly reaction medium. Four new copper(II) and nickel(II) complexes were synthesized by this ligand and amine ancillary ligands. (2) [Cu II (Ihqb)(Py)] (3) [Cu II (Ihqb)(4-Acpy)].4-Acpy (4) [Cu II (Ihqb)(3-Mepy)] (5) [Ni II (Ihqb)(bzlan)] The purity and spectral properties of the ligand and its copper and nickel complexes have also been investigated by UV-Vis, FT-IR, 1 H-NMR and elemental analysis. The structure of these complexes were determined by X-ray crystallography. The coordination geometry around the central metal ion in [Cu II (Ihqb)(Py)] complex is a distorted square pyramidal. The coordination geometry around the central metal ion in [Ni II (Ihqb)(bzlan)] and [Cu II (Ihqb)(4-Acpy)].4-Acpy complexes is a distorted square planar. The di-anionic Ihqb 2- acts as a tridentate ligand and occupies the basal positions through quinoline and amide nitrogen atoms and hydroxy oxygen atom. The amines coordinates as a monodentate ligand through nitrogen atom occupying one of the basal positions of the structure. The electrochemical behavior of Copper(II) complexes has been studied to evaluate the structural effects on the redox properties. Electrochemical studies reveal that the reduction process Cu II /Cu I is influenced by the nature of the ancillary amine ligand. Furthermore, nickel(II) complex was employed as a novel precursor to produce NiO by thermal decomposition. The product was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Energy-dispersive X-ray spectroscopy (EDS), infrared (IR) spectroscopy, thermogravimetric analysis (TG-DSC) and ultraviolet–visible (UV–Vis) spectroscopy