GREEN CHEMISTRY APPROACH IN SYNTHESIS OF 3,4-DIHYDROPYRIMIDINONE DERIVATIVES UNDER SOLVENT-FREE CONDITIONSAbstract
Simplify and improve conditions that have been used traditionally to carry out the conventional Biginelli reactioninvolves three-component one-pot condensation of an aldehyde, β-ketoester and urea or thiourea in ethanol under strong acidic condensation HCl for the synthesis of dihydropyrimidinone(DHPMs) and their sulphur analogue dihydropyrimidinthione derivatives which are act as (antibacterial, anti-inflamematory, antiviral, antitumor, antimalarial agents, hypnotics…. ect) by green chemistry approach. These reactions were performed by three-component condensation of different types of an aldehyde (benzaldehyde, acetaldehyde, furfural, cinnamaldehyde, and salicaldehyde), ethyl acetoacetate, and urea or thiourea at reflux temperature under solvent-free conditions without catalyst to afford the corresponding dihydropyrimidinones and dihydropyrimidinthione in excellent yields (76–96%). The advantages of this green chemistry approach the excellent yield, operational simplicity, short time, and the avoidance of the use of organic solvents and friendly preparation. Products were identified using physical and spectroscopic data (IR, 1HNMR, GC. Mass, UV).
Tawassl T. H. Hajelsiddig and A. E.M. Saeed*
Department of Chemistry, Collage of Science, Sudan University of Science and Technology, Sudan
14 October, 2014
18 December, 2014
14 April, 2015
01 May, 2015