Nano-Fe3O4/In: a heterogeneous magnetic nanocatalyst for synthesis of tetrazole derivatives under solvent-free conditions

Abstract

We prepared magnetically recoverable Fe3O4/In nanoparticles as a heterogeneous, economically, and nontoxic catalyst for producing 5-substituted-tetrazoles. A suitable, quick, and highly efficient method for synthesis of 5-substituted-1H-tetrazoles was proposed via a multicomponent reaction of aromatic aldehydes, malononitrile, and sodium azide in the presence of magnetic nanoparticles Fe3O4/In, under solvent-free conditions. Various characterization including XRD, FTIR, SEM, and EDX were performed to recognize the inherent features of the nanoparticles. Design expert software was used to optimize the reaction conditions including reaction temperature, catalyst content, and reaction time. The results show high efficiency, obtained by using a small amount of nanocatalyst. The advantages of this protocol including easy recovery of the nanocatalyst by an external magnet, ability to reuse for five runs without noticeable loss in activity, simple workup, solvent-free, and mild reaction conditions making it interesting from a financial and environmental point of view.