微波辐射CdC1_2催化合成3,4-二氢嘧啶-2-酮

Synthesis of 3,4-dihydropyrimidin-2-ones catalyzed by cadmium chloride under microwave irradiation

在微波辐射及无溶剂的条件下,氯化镉催化芳香醛、β-酮酸酯和尿素发生Biginelli缩合反应合成了系列3,4-二氢嘧啶-2-酮类化合物.结果表明,当n（苯甲醛）∶n（β-酮酸酯）∶n（尿素）为1.0∶1.0∶1.5,催化剂用量为芳香醛的12%,微波功率280 W,辐射时间5 min,3,4-二氢嘧啶-2-酮的收率高达85%～95%.该合成反应条件温和,反应时间短,操作简便,产率高,是一种环境友好型催化反应.

3,4-dihydropyrimidinones derivatives were synthesized in high yields by microwave-assisted Biginelli condensation from aldehyde,β-keto ester and urea under solvent-free conditions catalyzed by cadmium chloride. The results indicated that the yields of the 3,4-dihydropyrimidine-2-ones were up to 85%- 95 % with the microwave irradiation power 280 W, irradiation time 5 min,mole ratios n （aldehyde） ： n （β- keto ester） ： n （urea） =1.0 ： 1.0 ： 1.5,mole ratio of the catalyst and aldehyde was 0. 12 ： 1. This process had the advantages of simple workup, short reaction time, high yield,mild and environment friendly. The products were characterized by elemental analysis,IR and 1H NMR.