Eutectic Mixture Choline Chloride–Chloroacetic acid: a New and Efficient Catalyst for Synthesis of 3,4-Dihydropyrimidin-2-ones

Deep Eutectic Solvents (DES) with the properties of an ionic liquid can be formed between choline chloride and chloroacetic acid in a 1:1 molar ratio. In this paper, we discuss our success in synthesizing dihydropyrimidinones employing choline chloride: chloroacetic acid as catalyst. The advantage of using DES is in its ability to act as a solvent and catalyst simultaneously for the synthesis of dihydropyrimidinones via one-pot multi-component reaction of ethyl acetoacetate, aldehyde and urea. The results showed that choline chloride: chloroacetic acid based DES is the best catalyst and is successfully applicable to a wide range of aldehydes with high yields (70–95%) and short reaction times (5-75 min). The deep eutectic solvent can be easily recycled and reused.