Page 131 - 《精细化工》2020年第4期
P. 131
第 37 卷第 4 期 精 细 化 工 Vol.37, No.4
202 0 年 4 月 FINE CHEMICALS Apr. 2020
催化与分离提纯技术
氯铝酸盐双阳离子液体催化合成乙氧基
亚甲基丙二酸二乙酯
*
孙林慧,吕新宇,刘洪朔,邱 滔
(常州大学 石油化工学院,江苏 常州 213164)
摘要:以 N-烷基咪唑和二氯烷烃为原料,经过取代反应合成氯化咪唑 盐,添加 AlCl 3 络合制备了 7 种氯铝酸
盐双阳离子液体。以制备的离子液体为催化剂,通过原甲酸三乙酯和丙二酸二乙酯之间的缩合反应合成乙氧基
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亚甲基丙二酸二乙酯。采用 IR 对离子液体的酸度进行测定,通过 AlNMR 检测离子液体中铝的形态来分析提
出的反应机理。考察了催化剂种类、催化剂用量、反应物物质的量比、反应温度、反应时间及催化剂循环次数
对反应的影响。得到的最佳工艺条件为:以 1,6-双(N-甲基咪唑基)己烷氯铝酸盐离子液体[C 6 (Mim) 2 ]Cl 2 -4AlCl 3
作为催化剂,用量为 0.8%(以丙二酸二乙酯物质的量计),原甲酸三乙酯、丙二酸二乙酯和乙酸酐物质的量比
为 1.75∶1.00∶2.50,反应温度 100 ℃反应 2 h 后 140 ℃反应 6 h。该条件下,丙二酸二乙酯的转化率高达 98%,
目标产物的选择性和收率分别为 98%和 97%。
关键词:氯铝酸盐双阳离子液体;乙氧基亚甲基丙二酸二乙酯;缩合反应;机理;催化技术
中图分类号:O623.624 文献标识码:A 文章编号:1003-5214 (2020) 04-0765-08
Synthesis of ethoxymethylenemalonate diethyl ester catalyzed by
chloroaluminatedication ionic liquids
*
SUN Linhui, LÜ Xinyu, LIU Hongshuo, QIU Tao
(School of Petrochemical Engineering, Changzhou University, Changzhou 213164, Jiangsu, China)
Abstract: A series of imidazolium chloride were synthesized via substitution reaction between N-alkylimidazole
and different dichloroalkanes. Then, AlCl 3 was added to complex to prepare seven chloroaluminatedication
ionic liquids. The prepared ionic liquids were used to catalyze the condensation reaction between
triethylorthoformate and diethyl malonate to synthesize ethoxymethylenemalonate diethyl ester. The acidity
of ionic liquids were measured by IR. The proposed reaction mechanism was analyzed by detecting the
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morphology of aluminum in catalysts by AlNMR. The effects of catalyst type, catalyst dosage, molar ratio
of materials, reaction temperature, reaction time, and catalyst recyclability on the reaction were investigated.
The optimal process conditions were obtained. Under the conditions of 1,6-bis(N-methylimidazolyl) hexane
chloroaluminate ionic liquid [C 6(Mim) 2]Cl 2-4AlCl 3 as catalyst with its dosage of 0.8% (based on the molar
amount of diethyl malonate), n(triethylorthoformate) : n(diethyl malonate)∶n(acetic anhydride)=1.75∶
1.00∶2.50, 100 ℃ for 2 h, and 140 ℃ for 6 h. Under these conditions, the conversion rate of diethyl
malonate reached up to 98%, the selectivity and yield of target product were 98% and 97%.
Key words: chloroaluminatedication ionic liquids; ethoxymethylenemalonate diethyl ester; condensation
reaction; mechanism; catalysis technology
[6]
乙氧基亚甲基丙二酸二乙酯(EMME)是合成 氯亚甲基丙二酸二乙酯为原料来制备 ,现有工艺
[3]
杂环化合物,如:嘧啶衍生物 [1-2] 、吡啶衍生物 、 由原甲酸三乙酯(OFE)和丙二酸二乙酯(MDE)
[7]
1,2,4-三氮杂环 [4-5] 等的关键原料。早期以乙醇和 2- 的缩合来制备 。该工艺中使用多种催化剂如 ZnCl 2、
收稿日期:2019-11-08; 定用日期:2020-01-13; DOI: 10.13550/j.jxhg.20191059
作者简介:孙林慧(1995—),女,硕士生。联系人:邱 滔(1967—),男,研究员,E-mail:qiutao@cczu.edu.cn。