采用溶胶-凝胶法制备H3PW6Mo6O40/SiO2催化剂,以苯甲醛,乙酰乙酸乙酯和尿素为原料,无水乙醇为溶剂催化合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮,研究结果表明:反应物的摩尔比、反应温度、催化剂用量和反应时间是影响4-苯基-6...采用溶胶-凝胶法制备H3PW6Mo6O40/SiO2催化剂,以苯甲醛,乙酰乙酸乙酯和尿素为原料,无水乙醇为溶剂催化合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮,研究结果表明:反应物的摩尔比、反应温度、催化剂用量和反应时间是影响4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮合成收率的重要因素.当n(苯甲醛)∶n(乙酰乙酸乙酯)∶n(尿素)=1.0∶1.2∶1.5,反应温度为90℃,催化剂的用量占反应物料总质量的1.5%,反应时间为75min时,产品收率可达70.3%.通过熔点、IR、1 H NMR和MS对合成目标化合物进行了表征确认.展开更多
A new environmental friendly catalyst,HaSiWrMo6O40/PAn was prepared and identified by means of FT-IR,XRD and TG/DTA.The optimum conditions have been found,that was,mass ratio of m(PAn):m(HaSiW6Mo6On.)was 1:1.25,volume...A new environmental friendly catalyst,HaSiWrMo6O40/PAn was prepared and identified by means of FT-IR,XRD and TG/DTA.The optimum conditions have been found,that was,mass ratio of m(PAn):m(HaSiW6Mo6On.)was 1:1.25,volume of methanol was 20 mL,and the reflux reaction time was 2h.The structural identity of Keggin units was preserved after the incorporation into polyaniline matrix.H4SiW6Mo6040/PAn was used as catalyst in catalytic synthesis of acetals and ketals.Effects of n(aldehyde(ketone)):n(glycol),catalyst dosage and reaction time on yield were investingated.Optimal conditions were:n(aldehyde(ketone)):n(glycol)=1.0:1.5;mass fraction of catalyst to reactants,0.5%;reaction time,1.0 h and cyclohexane as water-stripped reagent,15 mL.Under these conditions,yields of actels and ketals were 31.9%-91.6%.展开更多
文摘采用溶胶-凝胶法制备H3PW6Mo6O40/SiO2催化剂,以苯甲醛,乙酰乙酸乙酯和尿素为原料,无水乙醇为溶剂催化合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮,研究结果表明:反应物的摩尔比、反应温度、催化剂用量和反应时间是影响4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮合成收率的重要因素.当n(苯甲醛)∶n(乙酰乙酸乙酯)∶n(尿素)=1.0∶1.2∶1.5,反应温度为90℃,催化剂的用量占反应物料总质量的1.5%,反应时间为75min时,产品收率可达70.3%.通过熔点、IR、1 H NMR和MS对合成目标化合物进行了表征确认.
文摘A new environmental friendly catalyst,HaSiWrMo6O40/PAn was prepared and identified by means of FT-IR,XRD and TG/DTA.The optimum conditions have been found,that was,mass ratio of m(PAn):m(HaSiW6Mo6On.)was 1:1.25,volume of methanol was 20 mL,and the reflux reaction time was 2h.The structural identity of Keggin units was preserved after the incorporation into polyaniline matrix.H4SiW6Mo6040/PAn was used as catalyst in catalytic synthesis of acetals and ketals.Effects of n(aldehyde(ketone)):n(glycol),catalyst dosage and reaction time on yield were investingated.Optimal conditions were:n(aldehyde(ketone)):n(glycol)=1.0:1.5;mass fraction of catalyst to reactants,0.5%;reaction time,1.0 h and cyclohexane as water-stripped reagent,15 mL.Under these conditions,yields of actels and ketals were 31.9%-91.6%.
