| Abstract: |
Copper–zinc composite catalysts have emerged as promising heterogeneous catalysts for facilitating multicomponent organic reactions with enhanced selectivity and reusability. This empirical study presents a comprehensive investigation of a novel copper–zinc oxide (Cu-Zn-O) composite catalyst synthesized via the co-precipitation method and characterized using multiple analytical techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The catalyst was systematically evaluated for its catalytic performance in model multicomponent organic reactions, specifically the Knoevenagel condensation and Mannich-type reactions, under optimized conditions. Results demonstrated that the Cu-Zn-O composite exhibited superior catalytic activity compared to individual metal oxides, with conversion rates exceeding 95% under mild reaction conditions (60°C, 4 hours). The catalyst demonstrated excellent reusability, maintaining >90% catalytic activity over five consecutive catalytic cycles without significant leaching of metal species. Mechanistic investigations utilizing density functional theory (DFT) calculations revealed that the synergistic interaction between copper and zinc active sites facilitates favorable adsorption of reactants and promotes C-C bond formation. The heterogeneous nature of the catalyst, combined with its environmental benignity and cost-effectiveness, positions it as a promising alternative to homogeneous catalytic systems. This work establishes the fundamental basis for industrial-scale applications of copper–zinc composites in sustainable organic synthesis. |
