Copper (II) Complex Based on Salicylate and Bipyridine-Type Ligands: Synthesis, Characterizations, DFT Insights, and Molecular Docking Simulation

A new copper(II) salicylate complex [Cu(sal)(bpy)]4.5H2O with bulky substitution (sal = doubly deprotonated salicylic acid, bpy = 2,2’-bipyridine) has been synthesized. The structure of the copper complex was analyzed by FT-IR, TGA, and single-crystal X-ray diffraction (SC-XRD) studies. SC-XRD showed that the structure contained a mononuclear and a binuclear molecule together with water molecules. The coordination geometry around copper in the case of mononuclear and binuclear molecules is approximately square planar and square pyramidal, respectively. Supramolecular assembly was stabilized by O-H···O and C-H···O bonding along with $$\pi\cdot\cdot\cdot\mathrm\pi$$ interactions, which were explored in detail by Hirshfeld surface analysis in terms of interatomic contacts. Voids analysis predicted the mechanical stability of the crystal. The structural and geometric properties of both mononuclear and binuclear copper molecules were analyzed using DFT calculations at the B3LYP/LANL2DZ/6–311 g (d, p) level. Furthermore, the in silico anticancer potential of the complex was explored through molecular docking simulations against the VEGFR2 protein.