Agar Supported NiO NPs: A Sustainable Approach for synthesis of 3,4-dihydropyrimidin-2 (1H)-Ones in Aqueous Hydrotropic Media

A novel approach for the ultrasound-assisted synthesis of 3,4-dihydropyrimidin-2(1H)-ones was developed by using biodegradable supported nanoparticles in a hydrotropic aqueous medium. Agar-supported NiO nanoparticles (NiO@AG NPs) were synthesized by in-situ co-precipitation method and characterization by means of spectroscopic and microscopic techniques indicates that spherical NiO NPs successfully supported on the surface of agar with particle size 31.22 nm containing Carbon, Nickel and Oxygen as major elements. NiO@AG NPs exhibit higher activity for the synthesis of 3,4dihydropy-rimidin-2(1H)-ones in an aqueous medium by using hydrotropes with high (463.51 h-1) turn over frequency. Short reaction time, high efficiency, centrifugation-free method of separation of the catalyst, and column chromatography-free isolation of the product are the key factor of this protocol. The easy synthetic method and stable form of NiO nanoparticles supported on agar suggest that it could be an efficient material for water-based organic transformation on a large scale with high turnover frequency in the future. [GRAPHICS] .

Automated summary

A novel approach using biodegradable supported nanoparticles in a hydrotropic aqueous medium was developed for the ultrasound-assisted synthesis of 3,4-dihydropyrimidin-2(1H)-ones. Agar-supported NiO nanoparticles (NiO@AG NPs) with a particle size of 31.22 nm were successfully synthesized and exhibited high activity with a turnover frequency of 463.51 h-1 for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones. The short reaction time, high efficiency, catalyst separation without centrifugation, and product isolation without column chromatography are the key features of this protocol. The stable form and easy synthesis of NiO nanoparticles supported on agar suggest its potential as an efficient material for large-scale water-based organic transformations in the future.