Title : CuFe₂O₄@Agar@Cu₂O Nanocatalyst: A Sustainable Approach for Synthesizing 1,4-Benzodiazepines and 5-Aryl Tetrazoles
Abstract:
Recent developments in heterogeneous catalysis have focused on transition metal-based nanoparticles due to their accessibility and efficiency, particularly in synthesizing N-heterocyclic compounds. These Nitrogen-containing heterocycles are significant in medicine for their extensive biological activities, which arise from their stable conformations, interactions with biological molecules, and favorable charge distributions. This study introduces a novel, highly effective, and reusable nanocatalyst, CuFe2O4@agar@Cu2O, crafted through a straightforward method for the synthesis of key biological compounds like benzodiazepines and tetrazoles. The CuFe2O4 core is coated with agar, which effectively binds Cu2O, and the nanoparticles were characterized using XPS, P-XRD, FT-IR, Fe-SEM, EDAX, TGA, and nitrogen adsorption. The catalyst offers numerous benefits, including a broad range of substrates, mild reaction conditions, high yields, rapid reaction times, reusability, and improved green chemistry metrics. Specifically, CuFe2O4@agar@Cu2O showed excellent performance in synthesizing 1,4-benzodiazepines, used for treating conditions such as anxiety, insomnia, and seizures, and 5-aryl-1H-tetrazoles, which are important in drug development for cardiovascular diseases and as bioisosteres in drug design. The synthesis of 1,4-benzodiazepines from 2-halo benzaldehyde and 1,2-diamine, and 5-aryl-1H-tetrazoles from benzaldehyde, sodium azide, and hydroxylammonium chloride, demonstrated advantages over existing methods. These include the catalyst's reusability up to five times with minimal activity loss and environmentally friendly reaction conditions, with impressive metrics for 1,4-benzodiazepines and 5-aryl-1H-tetrazoles: low E-factors (0.55 and 0.82); low PMIs (1.55 and 1.82), high Reaction Mass Efficiency (66.52% and 70.43%), and high Carbon Efficiency (97% and 94%) respectively.