Catalyst-free Approach to Dihydropyrimidones Using Glycerol/Ethyl Lactate as a Recyclable and Biodegradable Promoting Medium

:: A variety of dihydropyrimidone compounds were synthesised using an effective one-pot, multicomponent, environmentally friendly reaction of aromatic aldehydes, urea/thiourea, ethyl acetoacetate, and glycerol/ethyl lactate. To the best of our knowledge, this is the first catalyst-free strategy for the synthesis of this key scaffold with medicinal chemistry applications. Other significant aspects of the current approach consist of the employment of glycerol/ethyl lactate as a biodegradable and environmentally friendly reaction medium-cum-promoter, the use of easily available substrates, moderate reaction conditions, ease of use, a wide substrate scope, a short reaction time, easy workup, and excellent yields, and atom efficiency, which make the disclosed procedure an excellent alternative to existing methods.