Synthesis and characterization of Fe₃O₄@THAM‐SO₃H as a highly reusable nanocatalyst and its application for the synthesis of dihydropyrano[2,3‐<i>c</i>]pyrazole derivatives

Abstract

In this work, a new, green and beneficial nanomagnetic catalyst was easily fabricated using sulfuric acid as an acidic group on Fe 3 O 4 nanoparticles coated with tris (hydroxymethyl) aminomethane (THAM). The synthesized catalyst was characterized by FT‐IR, TGA/DTG, XRD, TEM, EDS, VSM, and SEM analyses. Next, its catalytic activity was studied for the synthesis of dihydropyrano[2,3‐ c ]pyrazole derivatives. This catalyst has advantages such as high catalytic activity, non‐toxicity, easy separation from the reaction mixture using an external magnet and reuses for several times without significantly reducing in its catalytic activity.