Facile synthesis of tetrazolo[1,5-a]pyrimidine with the aid of an effective gallic acid nanomagnetic catalyst

The present work is the first report of nano-Fe3O4@SiO2-NH-gallic acid in multicomponent reactions as a catalyst. One-pot condensation of various aromatic aldehydes, beta-ketoesters and 5-aminotetrazole to deliver the desired tetrazolo[1,5-a]pyrimidine derivatives is investigated. It involves successful surface modification of Fe3O4@SiO2-NH2 as a potent magnetic support with a well-known natural acid which attracts considerable interests because of its applications in different sciences. This reusable magnetically separable nanocatalyst provides a convenient and reliable method for high yield tetrazole derivatives synthesis in short reaction times with wide variety range of the products and facile isolation. Acid grafting on the surface of amine-functionalized silica-coated magnetic nanoparticles confirmed by Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA) and energy-dispersive X-ray (EDX) analysis techniques. Structural characterization included scanning electron microscopy (SEM) images along with transmission electron microscopy (TEM) images and vibrating sample magnetometer (VSM) curve applied for morphology and magnetism type determination of the resulted nanocatalyst, respectively. (C) 2019 Elsevier Ltd. All rights reserved.