An efficient one-pot synthesis of 3,4-dihydropyrimidin-2(1H)ones by a green acidic ionic liquid catalyst under solvent-free conditions

The biginelli reaction, of the most useful multicomponent reactions, is particularly attractive because the resulting dihydropyrimidinones (DHPMs) display a wide range of biological activities, which has led to the development of a number of lead compounds based on that structural core. The dihydropyrimidinones are of increasing importance because of their promising activities as calcium channel blockers, antiviral, antibacterial and antihypertensive effects and α-1a-antagonists. Moreover, several alkaloids containing the DHPM unit have been isolated from marine sources, which also exhibit interesting biological properties. In this study, a green and efficient method is described for the solvent-free synthesis of 3,4-dihydropyrimidin-2(1H)ones through one-pot three-component condensation of ethylacetoacetate, an aromatic aldehyde, and urea using an amino acid ionic liquid as catalyst. This methodology offers several advantages such as high yields, easy experimental work-up procedure, low loading of catalyst and absence of toxic solvent

Keywords:

Biginelli reaction , Dihydropyrimidinones , Ionic liquid , one-pot , solvent-free