Magnetic Nano Dextrin: Nano-Fe3O4@dextrin/ BF3 as a Biocompatible Catalyst for the Synthesis of 3,4-dihydropyrimidin 2(1H)-ones

Dextrin nanoparticles are usually applied as biocompatible biopolymers. Natural catalysts such as nano dextrin have high catalytic activity. Dextrin has attracted researchers’ attention because of its unique chemical structure, water-solubility, biodegradability, biocompatibility, abundance, affordability, availability to produce the applied materials. On the other hand, dextrin is a suitable substrate for trifluoride ions, and some metal ions due to its hydroxyl groups. Thus, the nano-Fe3O4@dextrin/BF3 catalyst was synthesized with readily available, unique, and efficient capability. The synthesized catalyst was characterized by different techniques such as energy-dispersive X-ray (EDX) analysis, Fourier transforms infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) image, and thermogravimetric analysis (TGA). Then the effect of adding nano-Fe3O4@dextrin/BF3 to the reaction of aldehydes, ethyl acetoacetate, and urea was studied on the synthesis of 3,4-dihydropyrimidin-2(1H)-ones derivatives under solvent-free conditions using an electrical mortar-heater. The synthesis of 3,4-dihydropyrimidin-2(1H)-one derivatives was carried out at 70 ˚C using a negligible amount (30 mg) of catalyst, in a short time of 20 min with a very suitable yield of 80-92%.