Heterogenous copper(II) schiff-base complex immobilized mesoporous silica catalyst for multicomponent biginelli reaction

A Copper(II) Schiff-base complex immobilized mesoporous silica-41 (Copper-Schiff base@MCM-41) was synthesized using the ultrasonication method. The formation of material with expected morphological and structural features was confirmed with various characterization techniques including UV-DRS, FTIR, LXRD, SEM, EDAX, ICP-AES, HR-TEM, BET, TGA-DTA, and ESR analyses. Furthermore, the Copper-Schiff base@MCM-41 catalyzed Biginelli reaction has performed under an eco-friendly solvent approach at room temperature, achieving high product yield. After the completion of the reaction, the catalyst was easily recovered using the filtration method and reused for another reaction, maintaining comparable product yield up to five repetitive cycles without any major catalytic activity decay. The exhibition of excellent catalytic activity towards 3,4-dihydropyrimidone derivatives with high product yield in a short time at room temperature proved that the Copper-Schiff base@MCM-41 is a more effective heterogeneous catalyst toward the Biginelli reaction compared to other catalysts. The plausible reaction mechanism has proposed based on the study.

Automated summary

A Copper(II) Schiff-base complex immobilized mesoporous silica-41 (Copper-Schiff base@MCM-41) was synthesized and characterized using various characterization techniques. The catalyst showed excellent catalytic activity in the Biginelli reaction, achieving high product yield at room temperature. It could be easily recovered and reused for multiple cycles without significant loss of catalytic activity. The study proposed a plausible reaction mechanism.