Sono and nano: A perfect synergy for eco-compatible Biginelli reaction

Abstract

Abstract In this study, we evaluated the performance of nano-γ-Fe 2 O 3 –SO 3 H catalyst in the Biginelli reaction and synthesized 3,4-dihydropyrimidine-2-(1 H )-ones. This reaction was carried out under solvent-free and ultrasonic irradiation conditions and belonged to one-pot multicomponent reactions (MCRs) with an adopted aromatic aldehyde, ethyl acetoacetate, and urea as starting materials for the beginning of the reaction. The synthesized materials were efficient in synthesizing 3,4-dihydropyrimidine-2-(1 H )-ones via the Biginelli reaction under reaction conditions. Thus, the advantages of using nano-γ-Fe 2 O 3 –SO 3 H in the Biginelli reaction are short reaction time, high efficiency, green method, solvent free, and cost-effective. Furthermore, nano-γ-Fe 2 O 3 –SO 3 H as a heterogeneous catalyst can be recycled five times without significantly reducing catalytic activity.