A Convenient One-Pot Biginelli Reaction Catalyzed by Y(OAc)<sub>3</sub>: An Improved Protocol for the Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones and Their Sulfur Analogues
作者:Gopalakrishnan Aridoss、Yeon-Tae Jeong
DOI:10.5012/bkcs.2010.31.04.863
日期:2010.4.20
Yttrium(III) acetate hydrate-catalyzed novel synthesis of 3,4-dihydropyrimidin-2(1H)-(thio)one derivatives was achieved through one-pot three-component condensation of diversified aldehydes, β-ketoesters and urea or N-methylurea or thiourea with a molar ratio of 1:1:1.4. In comparison to the classical Biginelli approach, this catalytic method has the advantages of short reaction time and improved product
Substituent effect in photocatalytic oxidation of 2-oxo-1,2,3,4-tetrahydropyrimidines using TiO2 nanoparticles
作者:Hamid R. Memarain、Mahnaz Ranjbar
DOI:10.1016/j.molcata.2011.12.026
日期:2012.4
The semiconductor-sensitized oxidation of various 1-, 4- and 5-substituted 2-oxo-1,2,3,4-tetrahydropyrimidines was carried out in acetonitrile using TiO2 anatase nanoparticles. The aims of this study were to elucidate the effects of the nature of the substituents on the 1-, 4- and 5-positions of the heterocyclic ring, the type of the photocatalyst and the nature of solvent on the rate of reaction. The proposed electron-transfer mechanism is supported by the experimental results and also by the computational studies. (C) 2012 Elsevier B.V. All rights reserved.