Synthesis, structural analysis, DFT study, and catalytic performance of a glycine-Schiff base binuclear copper(ii) complex

Abstract

In this study, we report the synthesis and comprehensive characterization of a novel binuclear copper(II) complex (LCu) featuring a Schiff base ligand derived from glycine. The complex was synthesized through a one-pot method and characterized using various techniques, including single-crystal X-ray diffraction (SCXRD), FTIR spectroscopy, thermal analysis, UV-Vis spectroscopy, and electron paramagnetic resonance (EPR). SCXRD analysis revealed a distinctive dimeric structure, with each copper center displaying a slightly distorted square pyramidal geometry. Spectroscopic techniques (FTIR, UV-Vis, EPR) corroborated the coordination environment of the copper ions. Computational studies, including non-covalent interaction (NCI) analysis and time-dependent density functional theory (TD-DFT) calculations, provided further insights into the electronic structure and stability of the complex. Catalytic tests of LCu were conducted in two key reactions: olefin cyclopropanation and C–S cross-coupling. The cyclopropanation reaction showed high yields, outstanding chemoselectivity, and exceptional trans diastereoselectivity, with a trans/cis ratio exceeding 1000 : 1. The C–S cross-coupling reaction also exhibited high conversion rates (over 93%) and yields (above 92%). These findings underscore the efficiency and versatility of LCu as a catalyst, with potential applications in sustainable synthetic processes.