An eco-safe and solvent-free approach for clean and one-pot synthesis of 3,4-dihydropyrimidin-2-(1H)-one/thione derivatives using Zn(OAc)2.2H2O as an environmental friendly, readily and efficient catalyst

Abstract

An environmental friendly, economical and clean Biginelli approach in presence of readily available zinc acetate dihydrate (Zn(OAc)₂.2H₂O) to access biologically active 3,4-dihydropyrimidin-2-(1H)-ones/thiones derivatives via one-pot, three-component reaction of β-keto esters (methyl or ethyl acetoacetate), aromatic aldehyde (benzaldehye derivatives) and urea or thiourea in high to excellent yields has been studied. This solvent-free procedure is sustainable and advantageous compared to conventional methods due to short reaction times, one-pot procedure, easy handling, efficient, environmentally benign nature, low-cost and non-toxic catalyst, eco-friendly, ready availability of starting materials and no requirement of chromatographic purification. The products have been characterized by melting points and ¹H NMR spectroscopy.