A Brønsted Acid Ionic Liquid Immobilized on Fe3O4@SiO2 Nanoparticles as an Efficient and Reusable Solid Acid Catalyst for the Synthesis of 2,3-Dihydroquinazolin-4(1H)-ones
Mehdi Fallah‐Mehrjardi, Samaneh Kalantari
Abstract
Abstract In the present study, an efficient and magnetically recoverable Brønsted acid ionic liquid, 1-methyl-3-[3-(triethoxysilyl)propyl]-1H-imidazol-3-ium hydrogen sulfate, immobilized on the surface of Fe3O4@SiO2 magnetic nanoparticles (Fe3O4@SiO2–ImHSO4) has been used for a high-yield synthesis of 2,3-dihydroquinazolin-4(1H)-ones through the condensation of anthranilamide with aldehydes and ketones in EtOH at room temperature or under reflux. The significant features of the present protocol are short reaction times, high yields of products, ecofriendly reaction conditions, simple work-up, and reusability of the catalyst. The catalyst can be simply magnetically recovered and reused at least five times without considerable loss of its catalytic activity.