氨基乙酸催化一锅法合成3,4-二氢嘧啶-2(1H)-酮

用氨基乙酸作为催化剂在无任何溶剂的条件下催化合成3,4-二氢嘧啶-2(1H)-酮类化合物。考察了反应时间、催化剂的摩尔分数、反应物(苯甲醛、乙酰乙酸乙酯和脲或硫脲)的摩尔比和反应体系温度等条件对收率的影响和其它醛参与反应时的收率。结果表明,在苯甲醛、乙酰乙酸乙酯和脲或硫脲的摩尔比为1∶1∶1.5,催化剂(氨基乙酸)与苯甲醛的摩尔比0.05,无溶剂条件下水浴加热(90℃)并搅拌3 h,3,4-二氢嘧啶-2-(1H)-酮的收率可以达到80%。

One-Pot Synthesis of 3,4-Dihydropyrimidin-2(1H)-Ones Catalyzed by Amino Acetic Acid

Synthesis of 3,4-dihydropyrimidin-2(1H)-ones catalyzed by amino acetic acid under solvent-free conditions was studied.Effects of reaction time,mole fraction of the catalyst,mole ratio of the reactants and reaction temperature on the yield of 3,4-dihydropyrimidin-2(1H)-ones were investigated.Some other experiments with several different aldehydes as reactants were also carried out to study the effect on the product yield.The results show that the yield of 3,4-dihydropyrimidin-2(1H)-one can reach 80% under the reaction conditions that mole ratio of benzaldehyde,acetoacetic ester and urea is 1∶1∶1.5,mole ratio of the catalyst and benzaldehyde is 0.05∶1,reaction temperature is 90 ℃ in water-bath and the reactants are stirred continuously for 3 h.