范文编号:ZY114 范文字数: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%。 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
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