磷钨酸铜绿色催化合成缩醛(酮)及其催化活性测定

合成了绿色杂多酸盐催化剂磷钨酸铜;将环己酮、苯甲醛同乙二醇、1,2-丙二醇的缩合反应作为探针反应,测定了催化剂的催化活性,比较系统地考察了催化剂用量、物料配比、反应时间、带水剂用量等因素对反应产率的影响.结果表明:在底物醛(酮)用量0.2 mol、醛(酮)/乙二醇(1,2-丙二醇)摩尔比1.0/1.5、催化剂用量0.5 g、带水剂环己烷用量18 mL、一定温度下回流反应2.0 h,1,4-二氧螺4,5]癸烷产率为83.3%,3-甲基-1,4-二氧螺4,5]癸烷产率为89.7%,2-苯基-1,3-二氧环戊烷产率为66.7%,4-甲基-2-苯基-1,3-二氧环戊烷产率为78.5%.

Synthesis of Acetals and Ketals Catalyzed by Green Catalyst Copper Phosphotungstate and Determination of the Catalytic Activity

Copper phosphotungstate was synthesized as a green heteropoly acid catalyst. The condensation reactions among cyclohexanone （or benzaldehyde） and glycol （or propylene glycol） generating 1,4 dioxaspiro 4, 5] decane, 3-methyl-I, 4-dioxaspiro 4, 5] decane, 2-phenyl- 1,3-dioxolane and 4-methyl-2-phenyl-1,3-dioxolane were used as the probe reactions to determine the catalytic activity of copper phosphotungstate catalyst. The effects of the amount of catalyst, mole ratio of starting materials, reaction time, and amount of deaquation reagent on the synthesis yield were investigated, and the optimum reaction conditions were established. The optimized reaction were determined as： amount of starting material aldehyde （or ketone） 0.2 mol, molar ratio of aldehyde （or ketone）/glycol （or propylene glycol） 1.0/1.5, amount of catalyst 0.5 g, amount of cyclohexane deaquation reagent 18 mL, refluxing for 2.0 h at a certain temperature. Under the optimized reaction conditions, the target products 1,4-dioxaspiro 4,5] decane, 3-methyl-i, 4-dioxaspiro 4, 5] decane, 2-phenyl-1,3-dioxolane, and 4-methyl-2-phenyl-l,3-dioxolane were obtained at a yield of of 83.3%, 89.7%, 66.7%, and 78.5%, respectively.