H3 PW12 O40／TiO2－SiO2催化合成3，4－二氢嘧啶－2（1H）－酮衍生物

摘要

3, 4 -Dihydropy -rimidine -2 ( 1H ) -one was synthesized from substituted benzaldehyde, ethylacetoacetate and urea using H3 PW12 O40/TiO2 -SiO2 as a novel eco-friendly catalyst that prepared by a sol-gel technique.The influences of molar ratio of reactant, reaction temperature, catalyst dosage and reaction time were discussed.Experimental results showed that H3 PW12 O40/TiO2 -SiO2 is a good catalyst for synthesis of 3,4-dihydropy-rimidine-2(1H) -one.When the dosage of substituted benzaldehyde is 0.04 mol, and anhydrous ethanol as solvent,n(substituted benzaldehyde)∶n(ethyl acetoacetate)∶n(urea) =1.0∶1.0∶1.5, the quantity of catalyst is 1.5%quantity of the feed stock, and reaction temperature is 90℃, and reaction time 75 min, the yield of 3,4-dihydropyrimidine-2(1H)-one could reach 35.0%-89.2%.The catalyst and synthesis products were characterized by IR, XRD and 1H NMR, IR, MS, respectively.%以H3 PW12 O40／TiO2－SiO2为催化剂，取代苯甲醛、乙酰乙酸乙酯和尿素为原料，无水乙醇为溶剂合成3，4－二氢嘧啶－2（1H）－酮衍生物．探讨了原料物质的量比、反应温度、催化剂用量及反应时间对收率的影响．实验表明：固定取代苯甲醛的用量为0．04 mol和无水乙醇的量为15 mL的情况下，n（取代苯甲醛）∶n（乙酰乙酸乙酯）∶n（尿素）＝1∶1．0∶1．5，催化剂的用量占反应物料总质量的1．5％，反应温度为90℃，反应时间为75 min，分别以对羟基苯甲醛、对硝基苯甲醛、茴香醛、4－氯苯甲醛、对甲氧基苯甲醛分别代替苯甲醛，产品收率为35.0％－89.2％．催化剂和合成产品分别采用IR， XRD和1 H NMR， IR， MS手段进行表征．