Claisen缩合合成三氟乙酰乙酸乙酯

论文编号:ZY114    论文字数:9207,页数:22

 摘 要： 三氟乙酰乙酸乙酯是合成氟杂环医药和农药的中间体。本文阐述了以三氟乙酸乙酯和乙酸乙酯为原料，在碱性催化剂下进行Claisen缩合，并用质子酸进行中和，乙酰化等步骤合成三氟乙酰乙酸乙酯的方法。对合成三氟乙酰乙酸乙酯的反应条件进行了优化探讨，结果表明实验的最佳反应条件为：以环己烷为溶剂，1.2当量的金属钠为催化剂，反应物摩尔比为1：1.5，缩合反应时间为4小时，甲酸中和，以1当量的乙酰氯进行乙酰化，最后得到的收率为78%。
关键字：三氟乙酰乙酸乙酯；Claisen缩合; 乙酰化

Abstract: Ethyl-trifluoroacetoacetate is used as important intermediate in the synthesis of pharmaceutical or plant protection industry. This paper describe a way of preparation of  ethyl-trifluoroacetoacetate  by  following steps . In the first step, ethyl-trifluoroacetate condensed with ethyl acetate in the presence of alkaline catalyst. The follow steps are neutralization and acetylation, then optimize the reaction conditions of the preparation of  ethyl-trifluoroacetoacetate.  The study show that the optimal reaction conditions as following: cyclohexane as solvent, 1.2 equivalent of sodium for catalyst, reactant molar ratio is 1 : 1.5, condensation reaction for 4 hours, formic acid for neutralization and 1 equivalent of chloride for acetylation, the yield of ethyl-trifluoroacetoacetate is 78%.

Keywords:  Ehyltrifluoroacetoacetate;；Claisen condensation；Acetylation

目  录
中文摘要...............................................................Ⅰ
英文摘要...............................................................Ⅱ
目录...................................................................Ⅲ
1.绪论.................................................................1
   1.1 前言............................................................1
 1.2 研究现状........................................................2
      1.2.1以氢化钠作为催化剂.........................................2
      1.2.2以金属钠作催化剂...........................................2
      1.2.3以乙醇钠为催化剂...........................................2
 1.3 实验设计........................................................4
2.实验部分.............................................................5
 2.1 实验材料........................................................5
       2.1.1 实验试剂..................................................5
       2.1.2 实验仪器..................................................5
 2.2 反应原理........................................................6
 2.3 实验步骤........................................................6
       2.3.1 缩合......................................................6
       2.3.2 中和......................................................7
       2.3.3 乙酰化....................................................7
        2.3.4 分离纯化..................................................7
3.结果与讨论...........................................................8
   3.1 对缩合过程中各因素的探讨........................................8
       3.1.1不同催化剂对收率的影响.....................................8
       3.1.2不同催化剂量对收率的影响...................................8
       3.1.3不同溶剂对收率的影响.......................................9
       3.1.4 不同反应时间对收率的影响..................................10
 3.2 对中和过程中各因素的探讨........................................10
3.2.1不同酸对收率的影响........................................10
 3.3 对乙酰化过程各因素的探讨........................................11
3.3.1 不同乙酰氯量对收率的影响..................................11
 3.4 产物的表征......................................................12
 4.总结与展望............................................................15
 致谢....................................................................17
 参考文献................................................................18