A One Pot Green Synthesis of 3,4 Dihydropyrimidin-2-(1H)-ones/Thiones Catalyzed By MgO-ZrO2 Under Solvent-Free Conditions

An efficient green synthesis of 3,4-dihydropyrimidin-2-(1H)-ones/thiones (DHPMs) using MgO/ZrO2 as heterogeneous basic catalyst from an aldehyde, β-keto ester and urea/thiourea under solvent-free conditions is described. A variety of aldehydes were studied with β-keto ester and urea/thiourea giving good to excellent yield of corresponding 3,4-dihydropyrimidin-2-(1H)-ones/thiones. This protocol has advantage of excellent yield, reusability, inexpensive and short reaction time at room temperature. The synthesized catalyst can be reused up to 5 consecutive cycles without any decrease in the yield.