A novel magnetic acidic catalyst comprising Preyssler(H14[Na P5W30O110]) heteropoly acid support‐ed on silica coated nickel ferrite nanoparticles (Ni Fe2O4@Si O2) was prepared.The catalyst was characterized...A novel magnetic acidic catalyst comprising Preyssler(H14[Na P5W30O110]) heteropoly acid support‐ed on silica coated nickel ferrite nanoparticles (Ni Fe2O4@Si O2) was prepared.The catalyst was characterized by Fourier transform infrared,scanning electron microscopy,transmission electron microscopy,X‐ray diffraction,energy dispersive spectrum,VSM and particle size neasurement.Its catalytic activity was investigated for the synthesis of bis(dihydropyrimidinone)benzene and 3,4‐dihydropyrimidin‐2(1H)‐ones derivatives by the Biginelli reaction.With the catalyst,the reac‐tions occurred in less than 1 h with good to excellent yields.More importantly,the catalyst was easily separated from the reaction mixture by an external magnet and reused at least five times without degradation in the activity.展开更多
目的合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮。方法采用一锅法Biginelli反应以乙酰乙酸乙酯、苯甲醛和尿素为原料,H3PW12O40/SiO2为催化剂,无水乙醇为溶剂进行合成目标化合物。通过熔点,IR,1 H NMR和MS等测试手段对合成的...目的合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮。方法采用一锅法Biginelli反应以乙酰乙酸乙酯、苯甲醛和尿素为原料,H3PW12O40/SiO2为催化剂,无水乙醇为溶剂进行合成目标化合物。通过熔点,IR,1 H NMR和MS等测试手段对合成的目标化合物进行表征。结果探讨了反应温度、催化剂用量、反应时间和反应物的摩尔比对收率的影响。实验表明:固定苯甲醛用量为0.04mol的条件下,催化剂的用量占反应物料总质量的2.0%,n(苯甲醛)∶n(乙酰乙酸乙酯)∶n(尿素)=1∶1.5∶1.5,反应时间为90min,反应温度为90℃。在优化条件下,产品平均收率可达79.2%。结论溶胶凝胶法制备的H3PW12O40/SiO2是合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮的良好催化剂,具有催化剂用量少,催化活性高,可回收重复使用等特点。展开更多
基金Ferdowsi and Islamic Azad University,Mashhad and Bandar Abbas Branches for financial support
文摘A novel magnetic acidic catalyst comprising Preyssler(H14[Na P5W30O110]) heteropoly acid support‐ed on silica coated nickel ferrite nanoparticles (Ni Fe2O4@Si O2) was prepared.The catalyst was characterized by Fourier transform infrared,scanning electron microscopy,transmission electron microscopy,X‐ray diffraction,energy dispersive spectrum,VSM and particle size neasurement.Its catalytic activity was investigated for the synthesis of bis(dihydropyrimidinone)benzene and 3,4‐dihydropyrimidin‐2(1H)‐ones derivatives by the Biginelli reaction.With the catalyst,the reac‐tions occurred in less than 1 h with good to excellent yields.More importantly,the catalyst was easily separated from the reaction mixture by an external magnet and reused at least five times without degradation in the activity.
文摘目的合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮。方法采用一锅法Biginelli反应以乙酰乙酸乙酯、苯甲醛和尿素为原料,H3PW12O40/SiO2为催化剂,无水乙醇为溶剂进行合成目标化合物。通过熔点,IR,1 H NMR和MS等测试手段对合成的目标化合物进行表征。结果探讨了反应温度、催化剂用量、反应时间和反应物的摩尔比对收率的影响。实验表明:固定苯甲醛用量为0.04mol的条件下,催化剂的用量占反应物料总质量的2.0%,n(苯甲醛)∶n(乙酰乙酸乙酯)∶n(尿素)=1∶1.5∶1.5,反应时间为90min,反应温度为90℃。在优化条件下,产品平均收率可达79.2%。结论溶胶凝胶法制备的H3PW12O40/SiO2是合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮的良好催化剂,具有催化剂用量少,催化活性高,可回收重复使用等特点。