2-氟丙二酸二甲酯的绿色合成工艺

Green synthesis of dimethyl 2-fluoromalonate

开发了以碳酸二甲酯(DMC)和氟乙酸甲酯(FMA)为原料合成2-氟丙二酸二甲酯(FMM)的新工艺,研究了叔丁醇钾(C4H9OK)、叔丁醇钠(C4H9ONa)、甲醇钠(CH3ONa)、甲醇钾(CH3OK)和钠氢(NaH)等不同种类的碱对该克莱森酯缩合反应的催化活性,探讨了杂质生成的机理,并通过单因素实验和正交实验考察了物料配比、反应温度、物料滴加时间、碱的用量等因素对反应的影响。结果表明,当n(FMA):n(DMC):n(CH3ONa)=1:4:1.05,反应温度80℃,物料滴加时间3.0h时,反应的收率为71.0%,产品纯度为99.2%。

A new process for the synthesis of dimethyl fluoromalonate(FMM)from dimethyl carbonate(DMC)and methyl fluoroacetate(FMA)was developed.The catalytic activities of different alkalis including tert-butanol potassium(C4H9OK),tert-butanol sodium(C4H9ONa),sodium methanol(CH3ONa),potassium methanol(CH3OK)and sodium hydride(NaH)for the claisen condensation reaction were studied.The mechanism of impurity formation was discussed.The effects of material ratio,reaction temperature,dropping time and alkali dosage on the reaction were investigated by single factor experiments and orthogonal experiments.The results showed that under the follow conditions:FMA/DMC/CH3ONa molar ratio of 1:4:1.05,reaction temperature of 80℃and dropping time of 3.0 h,the yield of 2-fluoromalonate dimethyl ester was 71.0%with the purity of 99.2%.