超声法合成3,4-二氢嘧啶-2(1H)-酮衍生物

以取代芳醛（1a~1h），乙酰乙酸乙酯(2)和脲(3)为原料，MMT/CuCl₂为催化剂，乙醇为溶剂，在超声条件下经Beginelli反应合成了8个3,4-二氢嘧啶-2(1H)-酮衍生物（4a~4h），其结构经¹H NMR和IR确证。以4a为例，分别采用单因素法和正交实验法研究了催化剂、溶剂、反应温度、超声时间和物料比r［n(1a): n(2) :n(3)］对4a产率的影响。结果表明：在最优反应条件(1a 2.4 mol, r=1.2 : 1.0 : 1.0, MMT/CuCl₂20 mol%, EtOH 1 mL,于90 ℃超声15 min)下，4a产率88.4%。 MMT/CuCl₂循环使用3次，产率基本不变。

Ultrasonic Synthesis of 3,4-Dihydropyrimidin-2(1H) one Derivatives

An ultrasound-assisted synthetic method of 3,4-dihydropyrimidin-2(1H) one derivatives was developed, using aromaticaldehyde(1a~1h), ethylacetoacetate(2) and urea(3) as material, MMT/CuCl2 as catalyst and EtOH as solvent.The structures were confirmed by 1 H NMR and IR.Effects of catalysts, solvents, reaction temperature, ultrasonic time and molar ratio{rn(1a) ∶n(2) ∶n(3)]}on yield of 4a were investigaed by single factor experiment and orthogonal test, respectively.The re-sults indicated that yield of 4a was 88.4% under the optimized conditoins(1a 2.4 mol, r=1.2 ∶1.0 ∶1.0, MMT/CuCl2 20 mol%, EtOH 1 mL, reaction at 90℃for 15 min).The yield of 4a remain stable after MMT/CuCl2 recycling for three times.