利用相转移催化法合成乙酰氧基甲基—七甲基环四硅氧烷

Synthesizing Acetoxymethyl-heptamethylcyclotetrasiloxane with phase transfer catalysis

探讨了利用相转移催化法由八甲基环四硅氧烷合成乙酰氧基甲基—七甲基环四硅氧烷的方法 .从催化剂的选择 ,反应时间 ,反应温度 ,原料比 ,溶剂的选择等方面对该反应可能的最佳条件进行了初步探讨 .实验证明以四丁基硫酸氢铵为相转移催化剂 ,水为溶剂 ,用一氯甲基—七甲基环四硅氧烷与醋酸钾反应 ,可以在温和的条件下制备乙酰氧基甲基—七甲基环四硅氧烷 .反应条件 :一氯甲基—七甲基环四硅氧烷与醋酸钾的摩尔投料比 1∶1 .3 ,6 0℃回流 1 .5h较为适宜 .

It was described that the method of synthesizing Acetoxymethyl-heptamethylcyclotetrasiloxane from octamethylcyclotetrasiloxane by using phase transfer catalyst and preliminarily discusses the possible best conditions for the reaction such as the choice of catalyst, reaction time, reaction temperature, the ratio of reactants, and the choice of solution, etc. The experiment results show that Acetoxymethyl-heptamethylcyclotetrasiloxanel can be prepared under mild conditions in the reaction of monochlormethyl-heptamethylcyclotetrasiloxane to potassium acetate in the solution of water with tetrabutyl-ammonium acid sulfate as phase transfer catalyst. The reaction conditions are that the ratio of monochlormethyl-heptamethylcyclotetrasiloxane to potassium acetate is 1∶1.3(mol) and the suitable reflux is at 60*!℃ for 1.5 hours.