Eco-Friendly Synthesis of 3,4-Dihydropyrimidine-2(1H)-ones Using Ionic Liquid [Msim]Cl as a Catalyst and Development of Novel Derivatives

The Brønsted acidic ionic liquid 3-methyl-1-sulfonic acid imidazolium chloride, [Msim]Cl, serves as an environmentally friendly catalyst for the efficient synthesis of 3,4-dihydropyrimidine-2(1H)-ones from the aromatic aldehydes, β-keto esters, and urea. This method is not only eco-friendly, but also produces high-purity products with excellent efficiency. The synthesized compounds were further characterized by using spectroscopic techniques, such as IR, 1H NMR and 13C NMR spectroscopy. The proposed method offers additional advantages such as operational simplicity, shorter reaction times, and mild reaction conditions. Additionally, the catalyst exhibits good recyclability. These features collectively highlight the feasibility and sustainability of this ionic liquid catalyzed system in the organic synthesis.