Synthesis, crystal structure, theoretical studies and biological evaluation of nickel(II) complex derived from N2O2 tetradentate Schiff base

Abstract

In the present study we report the synthesis, characterization, biological studies of the N2O2 donor Schiff base ligand: N,N'-bis(2-hydroxypropiophenone)-1,2-ethanediamine L and its’ nickel(II) complex NiL. We used 1H and 13C NMR, FT-IR, Raman and UV–Vis spectroscopy for characterization, and the structure of the complex was determined by single crystal X-Ray crystallography. Hirshfeld surface analysis and two-dimensional fingerprint plots and energy frameworks of NiL were calculated to quantify the interatomic interactions present in the crystal. The evaluation of antioxidant capacities of the prepared compounds were realized by two different in vitro methods (DPPH; ABTS) and showed an average inhibition. The biological activity was predicted for nikel complex (NiL) using the PASS software. On the other hand, the structural, optical properties, static and dynamic hyperpolarizabilities of NiL, PdL and PtL are studied using DFT and TD-DFT methods. The results show that the geometry parameters and the simulated UV/Vis absorption spectra of the NiL are in excellent agreement with the experiment. Furthermore, the results obtained showed that ML (M = Ni, Pd and Pt) exhibits a high hyperpolarizability (at static and dynamic regime) and thus, becomes a promising candidate for second-order NLO materials.