无溶剂条件下,以硝酸铋为催化剂,芳香醛、β-酮酯和N-取代脲"一锅法"合成了一系列N1-取代的3,4-二氢嘧啶-2(1H)-酮衍生物.考察了原料用量、催化剂用量和反应温度对实验结果的影响.确定当芳香醛、β-酮酯和N-取代脲的摩尔比为1:1:1.3,催化剂用量为3 mol%,反应温度为80℃时,反应时间较短,产率较高.提出了可能的催化作用机理.产品结构经IR、1 H NMR、13 C NMR和元素分析进行表征.%N1-Substituted 3,4-dihydropyrimidin-2(1H)-ones derivatives were synthesized by an one-pot reaction of aromatic alde-hydes,β-ketoesters and N-substituted urea with Bi(NO3 )3 ·5H2 O as a catalyst under solvent-free conditions. The effects of the mo-lar ratio of reactants,amount of catalyst,and reaction temperature on the yields were investigated. The results showed that the higher products yields within short reaction time could be obtained when the optimal conditions were naromatic aldehyde : nβ-ketoesters :nN-substituted urea=1 : 1 : 1. 3,3 mol%Bi(NO3)3·5H2O and 80 oC. The probable reaction mechanism was proposed. The structures of the products were confirmed by IR,1 H NMR,13 C NMR and elemental analysis techniques.
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