Ionic Liquid-mediated Multi-component Reaction Towards the Synthesis of Dihydropyrimidones: An Environmentally Benign Green Protocol

Multi-component reaction (MCR) has notable benefits when compared to traditional linear-type synthetic methods, owing to its adaptable, convergent, and atom-efficient properties. Herein, this study reported the three-component reaction using ethylacetoacetate, aldehydes, and urea in one-step synthesis that provided the 3,4-dihydropyrimidin-2(1H)-ones in excellent yields, such as 5-(Ethoxycarbonyl)-4-(4-chlorophenyl)-6-methyl-3,4-dihydropyrimidin-2(1H)-one obtained up to 94% of yield. The conversion was led by a catalytic amount of sulfuric acid and ionic liquids as a recyclable green solvent at 80 °C. The recyclable activity of the catalytic system up to three cycles shows excellent yields, ranging from 88% to 94%. Research Highlights: • The manuscript reports synthesis of the dihydropyrimidone derivatives by a catalytic system conc. H2SO4 in Ionic Liquids. • Introduce the environment friendly protocol for the synthesis of dihydropyrimidones derivatives. • The presented method following the advantages: short reaction time, mild reaction conditions, and high yields. • The synthesized compounds were characterized by FT-IR, 1H/13C NMR, and Mass analysis.