硅钨钼杂多酸掺杂聚苯胺催化合成苹果酯

Catalytic synthesis of 2-methyl-2-ethyl acetoacetate-1, 3-dioxolane over H_4SiW_6Mo_6O_(40)/PAn

自制了硅钨钼杂多酸掺杂聚苯胺催化剂H4SiW6Mo6O40／PAn。以乙酰乙酸乙酯和乙二醇为原料合成苹果醋,较系统地研究了原料物质的量比、催化剂用量、反应时间诸因素对产品收率的影响。实验表明,合成苹果酯的适宜反应条件为n酯:n醇=1:1.9,催化剂的质量分数为o.8％,环己烷为带水剂,反应时间60min。上述条件下,苹果酯的收率为69.7％。

new environmentally friendly catalyst, H4SiW6Mo6 O40/Pan(Ⅳ) is prepared. 2- Methyl- 2- ethyl acetoacetate- 1, 3- dioxolane(Ⅰ) is synthesized from ethyl acetoacetate(Ⅱ) and ethylene glycol(Ⅲ) in the presence of Ⅳ. The influences of molar ratio of materials, mass fraction of catalyst, and reaction time on the product yield are discussed, and the optimum reaction conditions are obtained. Experimental results show that the optimum conditions are as follows:n (Ⅱ):n(Ⅲ)=1. 0:1.9, the mass fraction of catalyst is 0. 8%, cyclohexane is used as water carrier, and the reaction time is 60 min. Under the above mentioned conditions, the yield of I can reach 69.7%.