Efficient synthesis of ZnFe2O4 nanoparticles using grape juice and its use as catalyst for the synthesis of methylenebisamides

Nano zinc ferrite type of magnetic nanoparticles (MNPs) could catalyze organic reactions in a mild and environment friendly manner [1-3]. This work described a green and useful method for the preparation of ZnFe2O4 nanoparticles using chicken feet extract. This nano particles used as an efficient nanocatalyst for the synthesis of 1,3,5-triaryl-4,5-dihydro-1H-pyrazoles. The synthesis was carried out via a simple three-component reaction between arylaldehydes, arylmethylketones, and arylhydrazines in good to excellent yields in the precense of nano ZnFe2O4 in solvent-free conditions (Scheme 1). The reaction were carried out by first mixing benzaldehyde 1a (1 mmol), hydroxylamine hydrochloride (1 mmol), sodium hydroxide (1 mmol), nano ZnFe2O4 (0.15 mmol) (Nano zinc ferrite were synthesis via sol gel method using grape juice) and DMSO 3mL in 5 mL water as a one-pot reaction. Then the reaction mixture was stirred at 80 °C for 1 hour. The TLC monitoring of the reaction mixture clearly indicated the formation of N,N -methylenedibenzamide 2a in excellent yield. Afterward the residue was filtered and recrystallized in ethanol and then the product 2a was obtained. In conclusion, we have developed a practical, simple and efficient reaction for the synthesis of bisamides using nano zinc ferrite. The method has several advantages, including high yields of products, easy experimental work-up, and use of simple and available starting materials, high atom economy, eco-friendly and mild reaction conditions without the use of any catalyst and organic solvents.