WO2018090199A1 - 一种异佛尔酮的制备方法 - Google Patents

一种异佛尔酮的制备方法 Download PDF

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WO2018090199A1
WO2018090199A1 PCT/CN2016/105939 CN2016105939W WO2018090199A1 WO 2018090199 A1 WO2018090199 A1 WO 2018090199A1 CN 2016105939 W CN2016105939 W CN 2016105939W WO 2018090199 A1 WO2018090199 A1 WO 2018090199A1
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isophorone
quaternary ammonium
strong base
organic
imidazole
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PCT/CN2016/105939
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English (en)
French (fr)
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周章涛
徐俊烨
费安杰
谭传文
黄志宁
肖诗华
颜燕南
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广东莱佛士制药技术有限公司
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Priority to PCT/CN2016/105939 priority Critical patent/WO2018090199A1/zh
Publication of WO2018090199A1 publication Critical patent/WO2018090199A1/zh

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
    • C07C45/67—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton
    • C07C45/68—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by increase in the number of carbon atoms
    • C07C45/72—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by increase in the number of carbon atoms by reaction of compounds containing >C = O groups with the same or other compounds containing >C = O groups
    • C07C45/74—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by increase in the number of carbon atoms by reaction of compounds containing >C = O groups with the same or other compounds containing >C = O groups combined with dehydration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
    • C07C49/587—Unsaturated compounds containing a keto groups being part of a ring
    • C07C49/603—Unsaturated compounds containing a keto groups being part of a ring of a six-membered ring

Definitions

  • the invention relates to the technical field of organic chemical synthesis, in particular to a preparation method for catalytic synthesis of isophorone.
  • Isophorone (CAS: 78-59-1) is an important fine chemical raw material. It has a wide range of applications in the polymer industry and the pharmaceutical industry, with an annual output of tens of thousands of tons.
  • the compound was synthesized in the 19th century and began industrialization during the rapid development of the polymer industry in the 1960s. Then, with the worldwide demand for high-performance materials, pharmaceutical intermediates, pesticides and other industries, its market is fast. Growth, the current annual demand is up to tens of thousands of tons.
  • the current industrial production routes of isophorone are acetone condensation methods, which are specifically classified into liquid phase condensation and gas phase condensation.
  • the liquid phase condensation reported in the literature is a high pressure vessel in which a strong inorganic base such as sodium amide, calcium hydride, alkali metal or alkaline earth metal hydroxide is used as a catalyst and heated to a high temperature for condensation. Since the inorganic strong base is not easily soluble in acetone, in order to make the reaction proceed smoothly, a small amount of water is generally added. Since the reaction condensate is insoluble in water, the system gradually forms two phases, requiring intense stirring. The disadvantage of this type of synthesis is the low conversion rate and selectivity.
  • the gas phase condensation reported in the literature is that at a high temperature, acetone gas is reacted at a high temperature (200-300 degrees Celsius) through a solid phase catalyst such as a metal oxide, a metal hydroxide, a calcium aluminum composite, or a magnesium aluminum composite.
  • a solid phase catalyst such as a metal oxide, a metal hydroxide, a calcium aluminum composite, or a magnesium aluminum composite.
  • the advantage of this type of synthesis is that the conversion and selectivity are slightly better.
  • the disadvantages are high energy consumption, high catalyst preparation cost, and short catalyst life.
  • the present invention provides a preparation method of isophorone by using an organic imidazole quaternary ammonium base as a catalyst. Liquid phase synthesis of isophorone.
  • the invention relates to a method for preparing an organic catalyzed isophorone.
  • the acetone is used as a starting material, and under the catalytic action of a catalyst organic imidazole quaternary ammonium strong base, a liquid phase condensation reaction of acetone is carried out, and isophorone is obtained by distillation. Specifically, the following steps are included:
  • X step (1) - imidazole as a quaternary ammonium salt anion include Cl -, Br -, I - A; reaction solvent in step (1) used in the starting reactant for the next acetone.
  • the reaction solvent of the step (1) is the starting material of the reaction of the step (2), and the influence of other solvents and the reaction substrate can be avoided.
  • the base used in the step (1) is sodium hydroxide, sodium methoxide, sodium ethoxide or sodium t-butoxide, and preferably sodium methoxide.
  • the temperature of the exchange reaction is 0 to 30 ° C, preferably 10 to 20 ° C; and the exchange reaction time is 1 to 8 h, preferably 2 to 4 h.
  • organic imidazole-based quaternary ammonium strong base of the above condensation reaction has the following structure:
  • R1 and R2 in the formula are each an aliphatic chain substituent of 6 or less carbons.
  • the organic imidazole-based quaternary ammonium strong base can be dissolved in acetone as a reaction medium and a starting material, and the reaction can be smoothly carried out without adding water, thereby avoiding "the reaction condensate is insoluble in water, the system gradually forms two phases, and strong stirring is required. "Technical issues.” At the same time, since the organic imidazole-based quaternary ammonium strong base forms a whole reaction with the reactant, the conversion and selectivity of the condensation reaction are improved.
  • the R1 is a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a t-butyl group or a n-butyl group; and the R 2 is a methyl group.
  • the reaction medium and the starting material are both acetone, and the catalyst is added.
  • the organic imidazole-based quaternary ammonium strong base is used in a catalytic amount of 0.1 to 10 mol%, and the condensation reaction is carried out in an autoclave at a condensation reaction temperature of 140 to 180 ° C, the condensation reaction time is 5 to 24 h.
  • the purification of isophorone can be carried out continuously or intermittently, in a single stage or in multiple stages. Purification is preferably achieved by distillation, which is isolated and purified according to the difference in boiling point of the main product isophorone and by-products to give isophorone.
  • the catalyst added organic imidazole quaternary ammonium strong base The catalytic amount is 0.5 to 2 mol%, and the condensation reaction is carried out in a high pressure reactor, the condensation reaction temperature is 150 to 170 ° C, and the condensation reaction time is 7 to 12 hours.
  • the isophorone is prepared by the method for preparing isophorone provided by the invention, and the process adopts organic catalytic synthesis, and the conversion rate per single pass is more than 60%, and the selectivity is more than 70%. It has the characteristics of novel process, few steps and mild reaction conditions.
  • acetone and an organic imidazole-based quaternary ammonium strong base are subjected to a condensation reaction in the same solvent system, and after the reaction is carried out at a controlled temperature for a certain period of time, the selectivity of isophorone is substantially stabilized, and by-products formed by the reaction are different.
  • the method for preparing isophorone provided by the present invention by using an organic imidazole-based quaternary ammonium strong base to condense acetone into isophorone, greatly improving single-pass conversion rate, and achieving better selectivity and operation It is easy to control, has no special requirements for equipment, and has high reaction efficiency, which is suitable for large-scale production promotion.
  • the autoclave was installed, heated to 150 ° C and reacted for 6 hours. After cooling, the sample was taken for GC analysis, and the acetone conversion rate was 67%, and the selectivity was 69%. After removing acetone by atmospheric distillation, the product was subjected to vacuum distillation to obtain 28 g of isophorone in a yield of 38%.
  • the autoclave was installed, heated to 160 ° C and reacted for 7 hours. After cooling, samples were taken for GC analysis. The acetone conversion was 68% and the selectivity was 71%. After removing acetone by atmospheric distillation, the product was subjected to vacuum distillation to obtain 29.8 g of isophorone in a yield of 39%.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Catalysts (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

本发明公开了一种有机催化异佛尔酮的制备方法，以丙酮为起始原料，在催化剂有机咪唑系季铵强碱的催化作用下，丙酮发生液相缩合反应，经过蒸馏得到异佛尔酮。具体包括有机咪唑系季铵强碱的合成和异佛尔酮的合成。有机咪唑系季铵强碱能溶于作为反应介质和起始原料的丙酮当中，可以使得反应顺利进行。采用本发明提供的异佛尔酮的制备方法，合成异佛尔酮，工艺采用有机催化合成，单程转化率大于60％，选择性大于70％。本发明的异佛尔酮的制备方法具有工艺新颖，步骤少，反应条件温和等特点。

Description

一种异佛尔酮的制备方法 技术领域
本发明涉及有机化学合成的技术领域，尤其是涉及一种催化合成异佛尔酮的制备方法。
背景技术
异佛尔酮(CAS：78-59-1)是一种重要的精细化工原料。其在高分子工业、医药工业中有着广泛的应用，年产量高达数万吨。
该化合物在十九世纪被合成出来，在二十世纪六十年代高分子工业快速发展期间开始工业化，随后随着全世界对高性能材料、医药中间体、农药等行业的需求增长，其市场快速增长，目前年需求量高达数万吨。
异佛尔酮目前的工业生产路线均为丙酮缩合法，具体分为液相缩合和气相缩合。文献报导的液相缩合是在高压容器中，以无机强碱如氨基钠、氢化钙、碱金属或者碱土金属氢氧化物作为催化剂，加热到高温进行缩合。由于无机强碱不易溶于丙酮，为了使得反应顺利进行，一般要添加少量水。由于反应缩合物不溶于水，体系逐渐形成两相，需要强烈的搅拌。这类合成的弊端是转化率和选择性都低。
文献报导的气相缩合是在高温下，丙酮气体在高温(200-300摄氏度)通过金属氧化物、金属氢氧化物、钙铝复合物、镁铝复合物等固相催化剂进行反应。这类合成的优势是转化率和选择性略好。然而缺点是能耗高，催化剂制备成本高，催化剂寿命短。
综上所述，目前报导的合成异佛尔酮的工艺，无论使用液相合成还是气相合成，均存在收率和转化率不够满意，成本高等缺点。
发明内容
针对现有技术的不足，为改善异佛尔酮转化率低、选择性差、催化剂昂贵的问题，本发明提供了一种异佛尔酮的制备方法，通过使用有机咪唑季铵碱作为催化剂，进行异佛尔酮的液相合成。
本发明是通过以下技术方案进行实现的：
一种有机催化异佛尔酮的制备方法，以丙酮为起始原料，在催化剂有机咪唑系季铵强碱的催化作用下，丙酮发生液相缩合反应，经过蒸馏得到异佛尔酮。具体包括以下步骤：
(1)有机咪唑系季铵强碱的合成：
Figure PCTCN2016105939-appb-000001
(2)异佛尔酮的合成：
Figure PCTCN2016105939-appb-000002
步骤(1)中所述的X-为咪唑季铵盐的负离子，包括Cl-、Br-，I-的一种；步骤(1)中所用的反应溶剂为下一步的起始反应物丙酮。步骤(1)的反应溶剂为步骤(2)反应的起始原料，可以避免了其他溶剂和反应底物的影响。
步骤(1)所用的碱为氢氧化钠、甲醇钠、乙醇钠、叔丁醇钠的一种，优选为甲醇钠。其中，交换反应的温度为0～30℃，优选为10～20℃；交换反应的时间为1～8h，优选2～4h。
其中，上述缩合反应的有机咪唑系季铵强碱具有以下结构：
Figure PCTCN2016105939-appb-000003
结构式中的R1和R2分别为小于或等于6个碳的脂肪链取代基。有机咪唑系季铵强碱能溶于作为反应介质和起始原料的丙酮当中，可以使得反应顺利进行，而且不用添加水，避免了“反应缩合物不溶于水，体系逐渐形成两相，需要强烈的搅拌”的技术问题。同时，由于有机咪唑系季铵强碱和反应物形成整体反应，提高了缩合反应的转化率和选择性。
作为本发明的实验方案的一种优选方式，所述的R1为甲基、乙基、正丙基、异丙基、叔丁基、正丁基的一种；所述的R2为甲基、乙基、正丙基、异丙基、叔丁基、正丁基的一种。
在上述的步骤(2)中，反应介质和起始原料均为丙酮，所加入的催化剂有机咪唑系季铵强碱的催化用量为0.1～10mol％，缩合反应在高压反应釜中进行，缩合反应温度为140～180℃，缩合反应时间为5～24h。在高压反应完成后，对异佛尔酮的提纯可以连续地或者间歇地，单阶段或者多阶段地进行。提纯优选通过蒸馏实现，根据主产物异佛尔酮和副产物沸点的不同，分离提纯得到异佛尔酮。
作为本发明的实验方案的进一步优化，所加入的催化剂有机咪唑系季铵强碱 的催化用量为0.5～2mol％，缩合反应在高压反应釜中进行，缩合反应温度为150～170℃，缩合反应时间为7～12h。
基于上述的技术方案，本发明具有的技术效果为：
(1)采用本发明提供的异佛尔酮的制备方法，合成异佛尔酮，工艺采用有机催化合成，单程转化率大于60％，选择性大于70％。具有工艺新颖，步骤少，反应条件温和等特点。
(2)本发明将丙酮和有机咪唑系季铵强碱在同一溶剂体系中进行缩合反应，反应在控制的温度下进行一定时间后，异佛尔酮的选择性达到基本稳定，反应生成的副产物异丙叉丙酮和异丙酮醇少，基本没有多分子聚合产物，而且反应更容易控制，不需要严格控制反应终点；最后通过蒸馏，分离提纯得到主产物异佛尔酮。
(3)本发明提供的异佛尔酮的制备方法，通过使用有机咪唑系季铵强碱，使丙酮缩合成异佛尔酮，大大改善了单程转化率，并取得了较好的选择性，而且操作控制方便，对设备无特殊要求，反应效率高，适合规模化生产推广。
具体实施方式
为了便于本领域的技术人员理解，下面结合具体实施例对本发明作进一步说明，实施方式提及的内容并不限定本发明的范围。
实施例1
(1)制备有机咪唑季铵碱催化剂
取一100mL三颈烧瓶，在氮气保护下向其中依次加入氯化1,3-二甲基咪唑(1.33g，0.01mol)、丙酮(100mL，1.71mol)，然后加入30％的甲醇钠甲醇溶液(1.8g，0.01mol)，控制反应温度为15℃。待反应4h后，对反应液进行过滤，滤液装入250mL高压釜。
(2)异佛尔酮的合成
安装好高压釜，加热到180摄氏度，反应5小时。降温后，取样品进行GC分析，丙酮转化率为62％，选择性为71％。常压蒸馏除去丙酮后，产品进行减压精馏，得到异佛尔酮30g，收率为40％。
实施例2
(1)制备有机咪唑季铵碱催化剂
取一100mL三颈烧瓶，在氮气保护下向其中依次加入氯化1,3-二叔丁基咪 唑(4.30g，0.02mol)、丙酮(100mL，1.71mol)，然后加入50％的氢氧化钠水溶液(1.6g，0.02mol)，控制反应温度为20℃。待反应6h后，对反应液进行过滤，滤液装入250mL高压釜。
(2)异佛尔酮的合成
安装好高压釜，加热到150摄氏度，反应6小时。降温后，取样品进行GC分析，丙酮转化率为67％，选择性为69％。常压蒸馏除去丙酮后，产品进行减压精馏，得到异佛尔酮28g，收率为38％。
实施例3
(1)制备有机咪唑季铵碱催化剂
取一100mL三颈烧瓶，在氮气保护下向其中依次加入氯化1,3-二正丁基咪唑(3.22g，0.015mol)、丙酮(100mL，1.71mol)，然后加入30％的甲醇钠甲醇溶液(1.8g，0.01mol)，控制反应温度为18℃。待反应6h后，对反应液进行过滤，滤液装入250mL高压釜。
(2)异佛尔酮的合成
安装好高压釜，加热到160摄氏度，反应7小时。降温后，取样品进行GC分析，丙酮转化率为68％，选择性为71％。常压蒸馏除去丙酮后，产品进行减压精馏，得到异佛尔酮29.8g，收率为39％。
以上所述仅为本发明的优选实施例而己，不能被认为用于限定本发明的实施范围，尽管参照前述实施例对本发明进行了详细的说明，对于本领域的技术人员来说，其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分技术特征进行等同替换。凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。

Claims (6)

  1. 一种异佛尔酮的制备方法，其特征在于，起始原料丙酮在催化剂有机咪唑系季铵强碱的催化作用下，发生缩合反应生成异佛尔酮，具体包括以下步骤：
    (1)有机咪唑系季铵强碱的合成：
    Figure PCTCN2016105939-appb-100001
    所述的X-为咪唑季铵盐的负离子，包括Cl-、Br-，I-的一种；
    (2)异佛尔酮的合成：
    Figure PCTCN2016105939-appb-100002
    所述的有机咪唑系季铵强碱具有以下结构：
    Figure PCTCN2016105939-appb-100003
    结构式中的R1和R2分别为小于或等于6个碳的脂肪链取代基。
  2. 根据权利要求1所述的异佛尔酮的制备方法，其特征在于，所述的R1为甲基、乙基、正丙基、异丙基、叔丁基的一种；所述的R2为甲基、乙基、正丙基、异丙基、叔丁基的一种。
  3. 根据权利要求1所述的异佛尔酮的制备方法，其特征在于，所述的有机咪唑系季铵强碱的催化量为0.1～10mol％。
  4. 根据权利要求3所述的异佛尔酮的制备方法，其特征在于，所述的有机咪唑系季铵强碱的催化量为0.5～2mol％。
  5. 根据权利要求1所述的异佛尔酮的制备方法，其特征在于，所述的步骤(2)的缩合反应在高压反应釜中进行，所述的缩合反应温度为140～180℃，所述的缩合反应时间为5～24h。
  6. 根据权利要求5所述的异佛尔酮的制备方法，其特征在于，所述的缩合反应温度为150～170℃，所述的缩合反应时间为7～12h。
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JPS5416472A (en) * 1977-06-28 1979-02-07 Basf Ag Production of imidazole compound
US5202496A (en) * 1989-04-18 1993-04-13 Aristech Chemical Corporation Method of making isophorne
US20040026666A1 (en) * 2000-10-27 2004-02-12 Yves Chauvin Imidazolium salts and their use of these ionic liquids as a solvent
CN101219939A (zh) * 2008-01-17 2008-07-16 上海华谊丙烯酸有限公司 一种碱性离子液体催化合成羟基新戊醛的方法

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5416472A (en) * 1977-06-28 1979-02-07 Basf Ag Production of imidazole compound
US5202496A (en) * 1989-04-18 1993-04-13 Aristech Chemical Corporation Method of making isophorne
US20040026666A1 (en) * 2000-10-27 2004-02-12 Yves Chauvin Imidazolium salts and their use of these ionic liquids as a solvent
CN101219939A (zh) * 2008-01-17 2008-07-16 上海华谊丙烯酸有限公司 一种碱性离子液体催化合成羟基新戊醛的方法

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