One-pot synthesis of 3,4-dihydropyrimidin-2(1H)-ones using lanthanum chloride as a catalyst

An efficient synthesis of 3,4-dihydropyrimidinones using lanthanum chloride heptahydrate as a catalyst from an aldehyde, beta -keto ester and urea or thiourea in ethanol is described. Compared to the classical Biginelli reaction conditions, this new method consistently has the advantage of good yields (56-97%). (C) 2000 Elsevier Science Ltd. All rights reserved.