An Environment-friendly Magnetic Organo-Nanomaterial as a Potent Catalyst in Synthesis of Pyranopyrazole Derivatives

Background: In the recent times, organo-nano catalysis has emerged as a growing field in catalytic science with widespread applications in organic synthesis. In the present article, we have focused on the preparation of an organo-nano catalyst and its application in the synthesis of pyranopyrazole derivatives. Method: The catalyst was fabricated by the functionalization of vitamin B1 on silica coated ferrite (Fe2O3@SiO2) nanoparticles and was characterized by different analytical techniques viz., FT-IR, TGA, TEM, SEM, EDX, VSM and powder XRD. This organo-nano catalyst was employed for the one-pot synthesis of pyranopyrazole derivatives from aromatic aldehyde / isatin, malononitrile, hydrazine hydrate and ethyl acetoacetate in water-ethanol mixture at room temperature stirring condtion. Results: A library of pyranopyrazole derivatives was synthesized by using a simple, efficient and environmentally benign protocol. The products obtained were pure with considerably higher yields (87- 98%). The catalyst was easily retrieved from the reaction mixture and reused up to six runs without any significant decrease in its catalytic activity. Conculsion: A simple eco-friendly method, mild reaction conditions, high product yields, short reaction times, easy catalyst recovery and recyclability make this synthetic approach an efficient and sustainable protocol.