SO_4^(2-)/TiO_2-MoO_3催化剂催化合成缩醛(酮)

Acetalation and Ketalation Catalyzed by SO_4^(2-) /TiO_2 - MoO_3 Catalyst

以固体超强酸SO42-/TiO2-MoO3为催化剂,对以环己酮、丁酮、正丁醛、异丁醛和乙二醇、丙二醇为原料合成缩醛(酮)的反应条件进行了研究。实验表明,固体超强酸SO42-/TiO2-MoO3是合成缩醛(酮)的良好催化剂,较系统地研究了醛(酮)/醇摩尔比、催化剂用量、反应时间诸因素对产品收率的影响。最佳反应条件为:n(醇)/n(酮或醛)=1.3/1或1.5/1,催化剂用量为反应物料总质量的0.25％～1.5％,反应时间为1.0 h。在最佳反应条件下,环己酮-乙二醇缩酮的收率为82.7％,环己酮-1,2-丙二醇缩酮的收率为83.4％,丁酮-乙二醇缩酮的收率为74.1％,丁酮-1,2-丙二醇缩酮的收率为94.9％,丁醛-乙二醇缩醛的收率为68.1％,丁醛-1,2-丙二醇缩醛的收率为87.5％,异丁醛-乙二醇缩醛的收率为70.7％,异丁醛-1,2-丙二醇缩醛的收率为82.5％。

Catalytic activities of solid superacid 864 /TiO2 - MoO3 in synthesizing cyclohexanone ethylene ketal,cyclohexanone 1,2 - propanediol ketal, butanone ethylene ketal, butanone 1,2 - propanediol ketal,2 -propyl -1,3- dioxolane, 4 - methyl - 2 - isopropyl -1,3 - dioxolane, 2 - isopropyl -1,3 - dioxolane, and 4 -methyl - 2 - isopropyl -1,3 - dioxolane were studied. SO42- /TiO2 - MoO3 was demonstrated as an excellent catalyst. Optimum reaction conditions found were alcohol /aldehyde(ketone) mole ratio 1.3/1 or1. 5/1, mass ratio of catalyst used reactants 0. 25% - 1. 5% , and reaction time 1. 0 h. Under these conditions, yield of cyclohexanone ethylene ketal was 82. 7 % ; cyclohexanone 1,2- propanediol ketal 83.4%; butanone ethylene ketal,74.1% ;butanone 1,2- propanediol ketal,94.9% ;2 - propyl -1,3- dioxolane,68.1 % ;4 - methyl - 2 -isopropyl -1,3- dioxolane ,87.5% ; 2 - isopropyl -1,3 - dioxolane, 70. 7 % ; and 4 - methyl - 2 - isopropyl - 1, 3-dioxolane, 82.5%.