A One-Pot Synthesis of 3,4-Dihydropyrimidin-2-(1H)-ones from Primary Alcohols Promoted by Bi(NO3)3·5H2O in Two Different Media: Organic Solvent and Ionic Liquid
作者:Ahmad Reza Khosropour、Ahmad R. Khosropour、Mohammd M. Khodaei、Mojtaba Beygzadeh、Mahbubeh Jokar
DOI:10.3987/com-04-10257
日期:——
A new, simple and efficientprocedure for the one-pot conversion of alcohols instead of aldehydes to the corresponding 3,4-dihydropyrimidin-2(1H)-ones (DHPMs) with Bi(NO 3 ) 3 .5H 2 O as a commercially available, inexpensive, stable and non-toxic reagent in two media, acetonitrile (as an organic solvent) and tetrabutylammonium bromide (as an ionic liquid) is described. This one-pot oxidation-cyclocondensation
N-Butyl-N,N-dimethyl-α-phenylethylammonium bromide catalyzes efficiently the three component condensation reaction of an aromatic aldehyde, a β-ketoester and urea/thiourea under solvent free conditions at 100°C to afford the corresponding dihydropyrimidinone in high yield.
4-Dihydropyrimidin-2(1H)-one derivatives were synthesized using layered α-zirconium sulfophenylphosphonate as a recyclableheterogeneouscatalyst. Several classes of reagents, such as functionalized aromatic and aliphatic aldehydes, β-dicarbonyl derivatives and 2-aminobenzimidazole, were used to synthesize different 3,4-dihydropyrimidin-2(1H)-one derivativesundersolventfree conditions.Graphical Abstract
One-pot synthesis of dihydropyrimidinones catalysed by lithium bromide: an improved procedure for the Biginelli reaction
作者:Gourhari Maiti、Pradip Kundu、Chandrani Guin
DOI:10.1016/s0040-4039(02)02859-9
日期:2003.3
LiBr catalyses efficiently the three component condensation reaction of an aldehyde, a β-ketoester and urea in refluxing acetonitrile to afford the corresponding dihydropyrimidinones in high yield.
Polyaniline-bismoclite complex was used as an efficient catalyst for the three-component condensation reaction of an aldehyde, β-ketoester, and urea in ethanol to afford the dihydropyrimidinones in excellent yields. Furthermore, after completion of reaction the catalyst could be easily recovered and reused without affecting its activity.