摘要
经典的Biginelli反应用盐酸作催化剂,通常收率较低(20%~50%),而表面活性剂和质子酸协同催化能有效的促进Biginelli反应进行。以苯甲醛、β-酮酸酯和尿素三组分为反应物,再加入表面活性剂(β-环糊精)和盐酸,用乙醇作溶剂,缩合制备3,4-二氢嘧啶-2-酮。考察了反应物摩尔比、反应时间、β-环糊精的物质的量和不同表面活性剂等因素对收率的影响。结果表明,在苯甲醛、β-酮酸酯、尿素的摩尔比为1.0:1.2:1.5,β-环糊精的物质的量为2.5mmol,浓盐酸的体积为0.25mL,乙醇的体积为25mL,回流时间为8h的条件下,3,4-二氢嘧啶-2-酮收率达到92%.
The yield of the classical Biginelli reaction is low(20% -50% ) when hydrochloric acid is used as catalyst, but synergistic catalysis of surfactant combined with proton acid could accelerate the Biginelli reaction effectively. 3,4 Dihydropyrimidin- 2(1H) - ones was synthesized under the condition of β-cyclcxtextrin as surfactant combined with hydrochloric acid in ethanol solution, and the condensation substrates were benzaldehyde, β-ketoacid ester and urea, The effects of substrate mole ratio, reaction timc, the amount of β-cyclodextrin and other surfactants on the yields were investigated. The resuhs show that the yield of 3, 4 dihydropyrimidin 2(1H) ones is up to 92%, under the conditions of 1.0: 1.2:1.5 mole ratio of benzaldehyde, β - ketoacid ester and urea, 2.5 mmol β-cyclodextrin, 0.25 mL hydrochloric acid, 25 mL ethanol, and 8 hours refluxing time.
出处
《辽宁石油化工大学学报》
CAS
2006年第1期16-18,共3页
Journal of Liaoning Petrochemical University