JPS6339858A - Purification of phenylmaleimide - Google Patents
Purification of phenylmaleimideInfo
- Publication number
- JPS6339858A JPS6339858A JP61183352A JP18335286A JPS6339858A JP S6339858 A JPS6339858 A JP S6339858A JP 61183352 A JP61183352 A JP 61183352A JP 18335286 A JP18335286 A JP 18335286A JP S6339858 A JPS6339858 A JP S6339858A
- Authority
- JP
- Japan
- Prior art keywords
- phenylmaleimides
- carbon dioxide
- maleimide
- pressure
- phenylmaleimide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- IYMZEPRSPLASMS-UHFFFAOYSA-N 3-phenylpyrrole-2,5-dione Chemical compound O=C1NC(=O)C(C=2C=CC=CC=2)=C1 IYMZEPRSPLASMS-UHFFFAOYSA-N 0.000 title claims description 58
- 238000000746 purification Methods 0.000 title claims description 9
- 125000000217 alkyl group Chemical group 0.000 claims abstract description 4
- 229910052736 halogen Inorganic materials 0.000 claims abstract description 4
- 150000002367 halogens Chemical class 0.000 claims abstract description 4
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims abstract description 4
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 85
- 239000001569 carbon dioxide Substances 0.000 claims description 43
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 43
- 238000000034 method Methods 0.000 claims description 26
- 239000012043 crude product Substances 0.000 claims description 12
- 239000000126 substance Substances 0.000 claims description 7
- 125000003545 alkoxy group Chemical group 0.000 claims description 3
- 125000004432 carbon atom Chemical group C* 0.000 claims description 3
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 claims description 3
- 229910052739 hydrogen Inorganic materials 0.000 claims description 3
- 239000001257 hydrogen Substances 0.000 claims description 3
- 125000004435 hydrogen atom Chemical group [H]* 0.000 claims description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 2
- 229910052799 carbon Inorganic materials 0.000 claims description 2
- 239000000203 mixture Substances 0.000 abstract description 16
- -1 phenylmaleimide compound Chemical class 0.000 abstract description 14
- 230000000694 effects Effects 0.000 abstract description 5
- 150000001875 compounds Chemical class 0.000 abstract description 4
- 239000002994 raw material Substances 0.000 abstract description 3
- 239000003905 agrochemical Substances 0.000 abstract description 2
- 239000003814 drug Substances 0.000 abstract description 2
- 239000011347 resin Substances 0.000 abstract description 2
- 229920005989 resin Polymers 0.000 abstract description 2
- 230000003247 decreasing effect Effects 0.000 abstract 1
- 238000001556 precipitation Methods 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 16
- 229910001220 stainless steel Inorganic materials 0.000 description 11
- 239000010935 stainless steel Substances 0.000 description 11
- PEEHTFAAVSWFBL-UHFFFAOYSA-N Maleimide Chemical compound O=C1NC(=O)C=C1 PEEHTFAAVSWFBL-UHFFFAOYSA-N 0.000 description 10
- 239000013078 crystal Substances 0.000 description 10
- 239000002253 acid Substances 0.000 description 7
- 150000007513 acids Chemical class 0.000 description 7
- 238000000605 extraction Methods 0.000 description 7
- 238000010438 heat treatment Methods 0.000 description 7
- 239000000047 product Substances 0.000 description 7
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 description 6
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 6
- 239000003377 acid catalyst Substances 0.000 description 6
- 238000000354 decomposition reaction Methods 0.000 description 6
- 239000003960 organic solvent Substances 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 5
- 239000003085 diluting agent Substances 0.000 description 5
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 description 4
- 239000012535 impurity Substances 0.000 description 4
- 238000006116 polymerization reaction Methods 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- KPQOXMCRYWDRSB-UHFFFAOYSA-N 1-(2-chlorophenyl)pyrrole-2,5-dione Chemical compound ClC1=CC=CC=C1N1C(=O)C=CC1=O KPQOXMCRYWDRSB-UHFFFAOYSA-N 0.000 description 3
- LJDGDRYFCIHDPX-UHFFFAOYSA-N 1-(2-methoxyphenyl)pyrrole-2,5-dione Chemical compound COC1=CC=CC=C1N1C(=O)C=CC1=O LJDGDRYFCIHDPX-UHFFFAOYSA-N 0.000 description 3
- KCFXNGDHQPMIAQ-UHFFFAOYSA-N 1-(4-methylphenyl)pyrrole-2,5-dione Chemical compound C1=CC(C)=CC=C1N1C(=O)C=CC1=O KCFXNGDHQPMIAQ-UHFFFAOYSA-N 0.000 description 3
- HIDBROSJWZYGSZ-UHFFFAOYSA-N 1-phenylpyrrole-2,5-dione Chemical compound O=C1C=CC(=O)N1C1=CC=CC=C1 HIDBROSJWZYGSZ-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 238000009835 boiling Methods 0.000 description 3
- 238000004821 distillation Methods 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- YWODHBPFOGXUFX-UHFFFAOYSA-N 1-(3-hydroxyphenyl)pyrrole-2,5-dione Chemical compound OC1=CC=CC(N2C(C=CC2=O)=O)=C1 YWODHBPFOGXUFX-UHFFFAOYSA-N 0.000 description 2
- QPSIVQYERUUXJE-UHFFFAOYSA-N 1-(4-butoxyphenyl)pyrrole-2,5-dione Chemical compound C1=CC(OCCCC)=CC=C1N1C(=O)C=CC1=O QPSIVQYERUUXJE-UHFFFAOYSA-N 0.000 description 2
- YLJPMCJDTAPPRX-UHFFFAOYSA-N 1-(4-butylphenyl)pyrrole-2,5-dione Chemical compound C1=CC(CCCC)=CC=C1N1C(=O)C=CC1=O YLJPMCJDTAPPRX-UHFFFAOYSA-N 0.000 description 2
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 239000012024 dehydrating agents Substances 0.000 description 2
- FPYJFEHAWHCUMM-UHFFFAOYSA-N maleic anhydride Chemical compound O=C1OC(=O)C=C1 FPYJFEHAWHCUMM-UHFFFAOYSA-N 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 238000001953 recrystallisation Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 239000008096 xylene Substances 0.000 description 2
- RRXDDBJMCPRNNO-UHFFFAOYSA-N 1-(2-ethoxyphenyl)pyrrole-2,5-dione Chemical compound CCOC1=CC=CC=C1N1C(=O)C=CC1=O RRXDDBJMCPRNNO-UHFFFAOYSA-N 0.000 description 1
- CNDOSNMFHUSKGN-UHFFFAOYSA-N 1-(2-hydroxyphenyl)pyrrole-2,5-dione Chemical compound OC1=CC=CC=C1N1C(=O)C=CC1=O CNDOSNMFHUSKGN-UHFFFAOYSA-N 0.000 description 1
- QYOJZFBQEAZNEW-UHFFFAOYSA-N 1-(2-methylphenyl)pyrrole-2,5-dione Chemical compound CC1=CC=CC=C1N1C(=O)C=CC1=O QYOJZFBQEAZNEW-UHFFFAOYSA-N 0.000 description 1
- CUZZFWJPTIJWJL-UHFFFAOYSA-N 1-(2-propylphenyl)pyrrole-2,5-dione Chemical compound CCCC1=CC=CC=C1N1C(=O)C=CC1=O CUZZFWJPTIJWJL-UHFFFAOYSA-N 0.000 description 1
- 150000003923 2,5-pyrrolediones Chemical class 0.000 description 1
- AENZGWONVTXLRC-UHFFFAOYSA-N 2-(2,5-dioxopyrrol-1-yl)benzoic acid Chemical compound OC(=O)C1=CC=CC=C1N1C(=O)C=CC1=O AENZGWONVTXLRC-UHFFFAOYSA-N 0.000 description 1
- RKGHVIBNRQCMDP-UHFFFAOYSA-N 3-(3-hydroxyphenyl)pyrrole-2,5-dione Chemical compound OC1=CC=CC(C=2C(NC(=O)C=2)=O)=C1 RKGHVIBNRQCMDP-UHFFFAOYSA-N 0.000 description 1
- UJNLRBKIVGGVIP-UHFFFAOYSA-N 3-(4-methylphenyl)pyrrole-2,5-dione Chemical compound C1=CC(C)=CC=C1C1=CC(=O)NC1=O UJNLRBKIVGGVIP-UHFFFAOYSA-N 0.000 description 1
- IVGGIBCLIRGTRS-UHFFFAOYSA-N 3-methoxy-4-phenylpyrrole-2,5-dione Chemical compound O=C1NC(=O)C(OC)=C1C1=CC=CC=C1 IVGGIBCLIRGTRS-UHFFFAOYSA-N 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 125000005037 alkyl phenyl group Chemical group 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- YFNONBGXNFCTMM-UHFFFAOYSA-N butoxybenzene Chemical group CCCCOC1=CC=CC=C1 YFNONBGXNFCTMM-UHFFFAOYSA-N 0.000 description 1
- 238000004040 coloring Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 239000000539 dimer Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000005755 formation reaction Methods 0.000 description 1
- 238000001640 fractional crystallisation Methods 0.000 description 1
- FSQQTNAZHBEJLS-UPHRSURJSA-N maleamic acid Chemical compound NC(=O)\C=C/C(O)=O FSQQTNAZHBEJLS-UPHRSURJSA-N 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000012264 purified product Substances 0.000 description 1
- 239000013557 residual solvent Substances 0.000 description 1
- 238000007363 ring formation reaction Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 235000011121 sodium hydroxide Nutrition 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 238000003815 supercritical carbon dioxide extraction Methods 0.000 description 1
- 230000002747 voluntary effect Effects 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/54—Improvements relating to the production of bulk chemicals using solvents, e.g. supercritical solvents or ionic liquids
Landscapes
- Pyrrole Compounds (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は新規なフェニルマレイミド類の精製方法に関す
る。詳しくは、超臨界状態の二酸化炭素を用いてフェニ
ルマレイミド類の粗製物からフェニルマレイミド類を抽
出分離するフェニルマレイミド類の精製方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a novel method for purifying phenylmaleimides. Specifically, the present invention relates to a method for purifying phenylmaleimides by extracting and separating phenylmaleimides from a crude product of phenylmaleimides using carbon dioxide in a supercritical state.
フェニルマレイミド類は樹脂原料、医薬品、農薬等の原
料として広く使用されている。Phenylmaleimides are widely used as raw materials for resins, pharmaceuticals, agricultural chemicals, etc.
（従来技術）
フェニルマレイミド類を製造する方法としては各種のも
のが知られている。一般的なものとしては、
（１） 無水マレイン酸とアミン化合物とを有機溶媒
中で反応させ生成するマレインアミド酸類を単離し、単
離したマレインアミド酸類を無水酢酸のような脱水剤を
用いてイミド化させる方法が米国特許用２，４４４．５
３６号明細書に開示されている。(Prior Art) Various methods are known for producing phenylmaleimides. In general, (1) maleic anhydride and an amine compound are reacted in an organic solvent to isolate maleamic acids, and the isolated maleamic acids are treated with a dehydrating agent such as acetic anhydride. The imidization method is US Patent No. 2,444.5
It is disclosed in the specification of No. 36.
■ 単離したマレインアミド酸類をトルエン、キシレン
、クロロベンゼンなどの有償溶剤を稀釈剤として用い、
酸触媒の存在下に加熱してイミド化させる方法が特公昭
５７−４２０４３号公報明細書に開示されている。■ Isolated maleamic acids are diluted with a paid solvent such as toluene, xylene, or chlorobenzene as a diluent.
A method of imidization by heating in the presence of an acid catalyst is disclosed in Japanese Patent Publication No. 57-42043.
Ｇ） 稀釈剤を用いずに７レインアミド酸類を酸触媒の
存在下に直接加熱してイミド化させる方法が特開昭４７
−２７９７４号公報明細書に開示されている。G) A method of imidizing 7-reinamide acids by directly heating them in the presence of an acid catalyst without using a diluent was disclosed in JP-A-47.
It is disclosed in the specification of Japanese Patent No.-27974.
（４） 生成したマレインアミド酸類を有機溶媒から
単離することなしにこの反応Ｕ合物に酸触媒を添加して
イミド化する方法が特公昭５１−４００７８号、特開昭
５３−６８７７０＠および特公昭５７−４２０４３号各
公報明細書等に数多く開示されている。(4) A method of imidizing the generated maleamic acid by adding an acid catalyst to the reaction U compound without isolating it from the organic solvent is disclosed in Japanese Patent Publication No. 40078/1982, Japanese Patent Application Laid-Open No. 68770/1987, and There are many disclosures in the specifications of Japanese Patent Publication No. 57-42043.
しかしながらこれらの何れのフェニルマレイミド類の製
造方法においても問題があり、イミド化反応の過程にお
いて無視しえない母の副生成物が生成し、高純度のフェ
ニルマレイミド類を得ようとすれば精製する必要がある
。However, there are problems with any of these methods for producing phenylmaleimides, as non-negligible parent by-products are produced during the imidization reaction, and purification is required to obtain highly pure phenylmaleimides. There is a need.
従来、フェニルマレイミド類の精製方法としては、
（１） 反応液を大量の冷水中へ注入して、析出する
結晶をン戸別し、この結晶を更に多量の水で洗浄したり
、或いは稀薄な炭酸ナトリウム水溶液や苛性ソーダ水溶
液で洗浄したのち乾燥させる方法が特開昭５５−１４９
２５３号公報明細書に開示されている。Conventionally, methods for purifying phenylmaleimides include: (1) Injecting the reaction solution into a large amount of cold water, separating the precipitated crystals, and washing the crystals with an even larger amount of water, or diluted carbonic acid. A method of washing with a sodium aqueous solution or a caustic soda aqueous solution and then drying is disclosed in JP-A-55-149.
It is disclosed in the specification of Japanese Patent No. 253.
■ フェニルマレイミド類含有の有機溶媒の反応液を稀
薄な弱アルカリ水溶液で中和後、水洗し、有機溶媒を分
離する方法が特開昭５３−６８７７０号公報明細書に開
示されている。(2) JP-A-53-68770 discloses a method in which a reaction solution of an organic solvent containing phenylmaleimides is neutralized with a dilute aqueous weak alkaline solution and then washed with water to separate the organic solvent.
しかし、上記のような方法では、イミド化工程で生成す
る副生成物が樹脂状の物質やフェニルマレイミド類と同
様に水に不溶性の物質であるため高純度のフェニルマレ
イミド類を得ることは困難である。However, with the above method, it is difficult to obtain highly pure phenylmaleimides because the byproducts generated in the imidization process are resin-like substances and substances that are insoluble in water like phenylmaleimides. be.
（発明が解決しようとする問題点）
フェニルマレイミド類には蒸留による精製方法もあるが
、フェニルマレイミド類は沸点が高く、しかもその分子
内に反応性に富むエチレン型不飽和結合を有しているた
めに蒸留塔内で加熱されることにより重合、分解、着色
が促進される。(Problem to be solved by the invention) Phenylmaleimides can be purified by distillation, but phenylmaleimides have a high boiling point and have highly reactive ethylenically unsaturated bonds in their molecules. Therefore, polymerization, decomposition, and coloration are promoted by heating in the distillation column.
その結果、蒸留精製収率が低く、しかも分解によって生
成する不純物が製品に混入し、製品の品質を低下させて
いる。As a result, the distillation purification yield is low, and impurities generated by decomposition are mixed into the product, degrading the quality of the product.
一方、再結晶法または分別結晶法ではフェニルマレイミ
ド類の粗製物に含まれている不純物等の分離が十分に行
なえず、しかも溶媒の除去に多大のエネルギーを要し、
溶媒の完全な除去が不可能であるなど、従来の技術では
精製収率、品質、純度の点で満足のできる製品を得るこ
とが困難であった。On the other hand, the recrystallization method or the fractional crystallization method cannot sufficiently separate impurities contained in the crude phenylmaleimides, and furthermore, a large amount of energy is required to remove the solvent.
With conventional techniques, it has been difficult to obtain products that are satisfactory in terms of purification yield, quality, and purity, as it is impossible to completely remove the solvent.
本発明者等は上記問題点を解決するため鋭意検討した結
果、フェニルマレイミド類がそのダイマー、重合高分子
、着色物質など、フェニルマレイミド類の粗製物に含ま
れる不純物に比較し、格段に超臨界二酸化炭素への溶解
度が大きく、そのためフェニルマレイミド類の粗製物に
超臨界状態の二酸化炭素を接触させることにより、フェ
ニルマレイミド類の粗製物から主としてフェニルマレイ
ミド類を超臨界状態の二酸化炭素に抽出溶解させ、フェ
ニルマレイミド類の溶解度が温度または／および圧力を
低下させることによって著しく低下することを利用して
高純度のフェニルマレイミド類を分離回収できることを
見い出し、本発明を完成した。As a result of intensive studies to solve the above problems, the present inventors have found that phenylmaleimides are much more supercritical than impurities contained in crude products of phenylmaleimides, such as their dimers, polymerized polymers, and colored substances. It has a high solubility in carbon dioxide, so by bringing the crude phenylmaleimides into contact with carbon dioxide in a supercritical state, mainly phenylmaleimides are extracted and dissolved in the carbon dioxide in a supercritical state from the crude phenylmaleimides. discovered that high-purity phenylmaleimides can be separated and recovered by utilizing the fact that the solubility of phenylmaleimides is significantly reduced by lowering temperature and/or pressure, and completed the present invention.
（問題を解決するための手段）
本発明は
一般式（１）、
Ｈ−Ｃ
Ｉ
〔式中、Ｒは水素、ハロゲン、カルボキシル基、ヒドロ
キシル基、炭素数１〜６のアルキル基まｔこは炭素数１
〜６のアルコキシ基を示す。〕で示されるフェニルマレ
イミド類の粗製物に超臨界状態の二酸化炭素を接触させ
て得られる、フェニルマレイミド類を含有する二酸化炭
素からフェニルマレイミド類を分離回収することを特徴
とするフェニルマレイミド類の精製方法に関するもので
ある。(Means for Solving the Problems) The present invention is based on the general formula (1), H-C I [wherein R is hydrogen, halogen, carboxyl group, hydroxyl group, alkyl group having 1 to 6 carbon atoms] Carbon number 1
~6 alkoxy group is shown. Purification of phenylmaleimides, characterized by separating and recovering phenylmaleimides from carbon dioxide containing phenylmaleimides, which is obtained by contacting the crude product of phenylmaleimides shown in ] with carbon dioxide in a supercritical state. It is about the method.
本発明の超臨界状態の二酸化炭素は、温度３１゜１℃〜
２００℃、圧力が７４．２〜５００に９／ｃｍＧ、好ま
しくは温度４０〜１４０℃、圧カフ５〜３００Ｋｇ／ｃ
ｆｆｌＧの範囲が抽出条件として採用できる。The supercritical carbon dioxide of the present invention has a temperature of 31°1°C to
200℃, pressure 74.2-5009/cmG, preferably temperature 40-140℃, pressure cuff 5-300Kg/c
The range of fflG can be adopted as the extraction condition.
本発明の抽出条件は、温度および圧力が共に高い方がフ
ェニルマレイミド類の溶解度が大きく、抽出効率を向上
させることができる。Regarding the extraction conditions of the present invention, the higher the temperature and pressure are, the higher the solubility of phenylmaleimides is, and the extraction efficiency can be improved.
しかし抽出圧力を高めることは一方で高圧設備の費用の
増大を招き、経済性の問題を生じる。また抽出温度を上
げることは抽出目的物であるフェニルマレイミド類の重
合、分解、着色等の変質を促進させるものである。However, increasing the extraction pressure on the other hand increases the cost of high-pressure equipment, creating an economical problem. In addition, raising the extraction temperature promotes alterations such as polymerization, decomposition, and coloring of phenylmaleimide, which is the target of extraction.
一方、フェニルマレイミド類を含む二酸化炭素から、フ
ェニルマレイミド類を分離するには温度を下げ、または
／および圧力を下げ、その結果溶解度を下げることによ
ってフェニルマレイミド類のみを析出させる方法がある
。On the other hand, in order to separate phenylmaleimides from carbon dioxide containing phenylmaleimides, there is a method in which only phenylmaleimides are precipitated by lowering the temperature and/or pressure, thereby lowering the solubility.
本発明が対象とするフェニルマレイミド類の粗製物は従
来公知の製造方法によって得られるものである。すなわ
ち、原料マレインアミド酸類は通常無水マレイン酸とア
ミン類との反応により容易に得られるものであり、この
もののイミド化閉環反応としては、本明細書の従来技術
の項で既に記述したように、トルエン、キシレン、クロ
ロベンゼンなどの有機溶剤を稀釈剤として用いて酸触媒
の存在下加熱してイミド化させる方法、稀釈剤を用いな
いで、マレインアミド酸類を酸触媒の存在下に直接加熱
してイミド化させる方法、あるいは無水酢酸のような脱
水剤を用いてイミド化させる方法、酸触媒および安定剤
、金属含有化合物の存在下、有機溶媒を稀釈剤として用
い、加熱してイミド化させる方法などがあり、いずれの
方法によって製造されるフェニルマレイミド類の粗製物
も本発明の精製方法は優れた効果を与える。The crude phenylmaleimides targeted by the present invention are obtained by conventionally known production methods. That is, the raw material maleamic acids are usually easily obtained by the reaction of maleic anhydride and amines, and the imidization ring-closing reaction of these acids is performed by, as already described in the prior art section of this specification, A method of imidization by heating in the presence of an acid catalyst using an organic solvent such as toluene, xylene, or chlorobenzene as a diluent, or a method of imidizing maleamic acids by heating directly in the presence of an acid catalyst without using a diluent. or imidization using a dehydrating agent such as acetic anhydride, or heating to imidize using an organic solvent as a diluent in the presence of an acid catalyst, stabilizer, or metal-containing compound. The purification method of the present invention provides excellent effects on the crude phenylmaleimides produced by either method.
上述の方法によって得られるフェニルマレイミド類は例
えば、
一般式（１）
〔式中、Ｒは水素、ハロゲン、カルボキシル基、ヒドロ
キシル基、炭素数１〜６のアルキル基または炭素数１〜
６のアルコキシ基を示す。〕で表わされるものであり、
さらに具体的に例示するならば、Ｎ−７エニルマレイミ
ド、Ｎ−（クロロフェニル）マレイミド、Ｎ−（カルボ
キシフェニル）マレイミド、Ｎ−（ヒドロキシフェニル
）マレイミドそしてＮ−（メチルフェニル）マレイミド
、Ｎ−（エチルフェニル）マレイミド、Ｎ−（プロピル
フェニル）マレイミド、Ｎ−（ブチルフェニル〉マレイ
ミド、Ｎ−（ヘキシルフェニル）マレイミド等のＮ−（
アルキルフェニル）マレイミドが挙げられる。また、Ｎ
−（メトキシフェニル）マレイミド、Ｎ−（エトキシフ
ェニル）マレイミド、Ｎ−（ブトキシフェニル）マレイ
ミド、等のＮ−（アルコキシフェニル）マレイミドが挙
げられる。The phenylmaleimide obtained by the above method has, for example, the general formula (1) [wherein R is hydrogen, halogen, carboxyl group, hydroxyl group, alkyl group having 1 to 6 carbon atoms, or
6 shows an alkoxy group. ],
More specific examples include N-7enylmaleimide, N-(chlorophenyl)maleimide, N-(carboxyphenyl)maleimide, N-(hydroxyphenyl)maleimide, N-(methylphenyl)maleimide, N-(ethyl N-(phenyl)maleimide, N-(propylphenyl)maleimide, N-(butylphenyl>maleimide, N-(hexylphenyl)maleimide, etc.
alkylphenyl)maleimide. Also, N
-(Methoxyphenyl)maleimide, N-(ethoxyphenyl)maleimide, N-(butoxyphenyl)maleimide, and other N-(alkoxyphenyl)maleimides.
（作 用）
本発明によれば、超臨界二酸化炭素はフェニルマレイミ
ド類に対して高い溶解能を右する。そのため、高い沸点
を有するフェニルマレイミド類を、フェニルマレイミド
類の粗ツＪ物から比較的低い温度で溶解し抽出すること
ができる。そうすることによって、フェニルマレイミド
類はその分子内に反応性に富む二重結合を有するにもか
かわらず、抽出操作中に重合、分解、着色物質生成等に
よるフェニルマレイミド類の損失および品質劣化が起る
ことを防ぐことができる。(Function) According to the present invention, supercritical carbon dioxide has a high dissolving power for phenylmaleimides. Therefore, phenylmaleimides having a high boiling point can be dissolved and extracted from crude phenylmaleimides at a relatively low temperature. By doing so, even though phenylmaleimides have highly reactive double bonds in their molecules, loss and quality deterioration of phenylmaleimides due to polymerization, decomposition, formation of colored substances, etc. occur during extraction operations. This can be prevented.
また、超臨界二酸化炭素はフェニルマレイミド類に対し
てフェニルマレイミド類の粗製物中に含有される重合物
、分解物、着色物質等の不純物に比較して、格段に大き
な溶解能を有する。In addition, supercritical carbon dioxide has a much greater ability to dissolve phenylmaleimides than impurities such as polymers, decomposition products, and colored substances contained in crude products of phenylmaleimides.
したがって、超臨界二酸化炭素を使用することによって
、フェニルマレイミド類の粗製物からほとんどフェニル
マレイミド類のみを選択的に抽出することができる。さ
らには、フェニルマレイミド類の粗製物を超臨界二酸化
炭素抽出処理して得られるフェニルマレイミド類を含有
する二酸化炭素からフェニルマレイミド類を分離するに
は、単に温度または／および圧力を下げるだけで良く、
重合、分解等の起こる危険性のある加熱操作を必要とし
ない。Therefore, by using supercritical carbon dioxide, almost only phenylmaleimides can be selectively extracted from the crude phenylmaleimides. Furthermore, in order to separate phenylmaleimides from carbon dioxide containing phenylmaleimides obtained by subjecting crude phenylmaleimides to supercritical carbon dioxide extraction, it is sufficient to simply lower the temperature and/or pressure.
Does not require heating operations that may cause polymerization, decomposition, etc.
したがって、本発明によればフェニルマレイミド類の粗
製物に超臨界二酸化炭素を作用させることによって、フ
ェニルマレイミド類の純度・品質の良好なものをしかも
収率よく得ることができる作用を有する。Therefore, according to the present invention, phenylmaleimide having good purity and quality can be obtained in good yield by allowing supercritical carbon dioxide to act on the crude product of phenylmaleimide.
（実 施 例）
以下、本発明の実施例を示すが、本発明はこれらに限定
されるものでない。(Examples) Examples of the present invention will be shown below, but the present invention is not limited thereto.
実施例 １
Ｎ−フェニルマレイミド８８重量％およびその他１２重
通％の組成のフェニルマレイミドの粗製物４０．０ｇを
０．３１のステンレス製耐圧容器に仕込み、ガス吹き込
み口より、二酸化炭素を供給し、ステンレス製耐圧容器
内を温度５０℃、圧力２００に９／ｃｉＧに保ちながら
、一方のガス扱き出し口から連続的にＮ−フェニルマレ
イミドを含有する超臨界状態の二酸化炭素を扱き出し、
セパレーターで常温、大気圧とし二酸化炭素と抽出物３
４．４ｇとに分離した。Example 1 40.0 g of crude phenylmaleimide having a composition of 88% by weight of N-phenylmaleimide and 12% by weight of others was charged into a 0.31 stainless steel pressure-resistant container, and carbon dioxide was supplied from the gas inlet, While maintaining the inside of the stainless steel pressure vessel at a temperature of 50°C and a pressure of 200/9/ciG, supercritical carbon dioxide containing N-phenylmaleimide was continuously discharged from one gas outlet.
Carbon dioxide and extract 3 at room temperature and atmospheric pressure in a separator
It was separated into 4.4g.
得られた抽出物は黄色結晶であり、その組成はＮ−フェ
ニルマレイミド９８重世％、その他２重量％であった。The obtained extract was yellow crystals, and its composition was 98% by weight of N-phenylmaleimide and 2% by weight of other substances.
実施例 ２
Ｎ−（ｏ−クロロフェニル）マレイミド８５重Ｍ％およ
びその！１５１５重量組成の淡黄褐色のＮ−（０−クロ
ロフェニル）マレイミドの粗製物４０．０にｌを０．３
１のステンレス製耐圧容器に仕込み、ガス吹き込み口よ
り、二酸化炭素を供給し、ステンレス製耐圧容器内を温
度５０℃、圧力２００ Ｋｇ／ ｃｉ Ｇに保ちながら
、一方のガス扱き出し口から連続的にＮ−（ｏ−クロロ
フェニル）マレイミドを含有する超臨界状態の二酸化炭
素を央き出し、セパレーターで常温、大気圧とし二酸化
炭素と抽出物３１．２ｇとに分離した。 得られた抽出
物は淡黄色結晶であり、その組成はＮ−（０−クロロフ
ェニル）マレイミドが９６重量％であった。Example 2 N-(o-chlorophenyl)maleimide 85% by weight and its! 1515 A light yellowish brown crude product of N-(0-chlorophenyl)maleimide with a weight composition of 40.0 to 0.3
Carbon dioxide was supplied from the gas inlet, and while maintaining the inside of the stainless steel pressure container at a temperature of 50°C and a pressure of 200 Kg/ci G, it was continuously supplied from one gas outlet. Supercritical carbon dioxide containing N-(o-chlorophenyl)maleimide was taken out in the center and separated into carbon dioxide and 31.2 g of extract at room temperature and atmospheric pressure using a separator. The obtained extract was pale yellow crystals, and its composition was 96% by weight of N-(0-chlorophenyl)maleimide.
実施例 ３
Ｎ−（０−カルボキシフェニル
２重量％およびその他１８重量％の組成の淡黄褐色のＮ
−（〇ーカルボキシフェニル
の粗製物４０．ＯＱを０．３ｊ！のステンレス製耐圧容
器に仕込み、ガス吹き込み口より、二酸化炭素を供給し
、ステンレス製耐圧容器内を温度８０℃、圧力２５０Ｋ
ｇ／ｃｆｆｌＧに保ちながら、一方のガス扱き出し口か
ら連続的にＮ−（〇ーカルボキシフェニル）マレイミド
を含有する超臨界状態の二酸化炭素を抜き出し、セパレ
ーターで常温、大気圧とし二酸化炭素と抽出物２８．６
ＣＩとに分離した。Example 3 Light yellowish brown N-(0-carboxyphenyl 2% by weight and other 18% by weight composition)
-(〇-Pour 40.0Q of crude carboxyphenyl into a 0.3J! stainless steel pressure-resistant container, supply carbon dioxide from the gas inlet, and heat the inside of the stainless steel pressure-resistant container at a temperature of 80°C and a pressure of 250K.
While maintaining the temperature at g/cfflG, supercritical carbon dioxide containing N-(〇-carboxyphenyl)maleimide is continuously extracted from one gas handling outlet, and the carbon dioxide and extract are brought to room temperature and atmospheric pressure with a separator. 28.6
It was separated into CI and CI.
得られた抽出物は黄白色結晶であり、その組成はＮ−（
０−カルボキシフェニル）マレイミドが９６重量％であ
った。The obtained extract is yellowish-white crystals, the composition of which is N-(
0-carboxyphenyl)maleimide was 96% by weight.
実施例 ４
Ｎ−（ｍ−ヒドロキシフェニル）マレイミド８２重量％
およびその（ｌ！！１８［ｉｔ％の組成の黄褐色のＮ−
（ｍ−ヒドロキシフェニル）マレイミドの粗製物４０．
ＯＱを０．３１のステンレス製耐圧容器に仕込み、ガス
吹き込み口より、二酸化炭素を供給し、ステンレス製耐
圧容器内を温度６０℃、圧力２５０に９／ｃｔｉＧに保
ちながら、一方のガス扱き出し口から連続的にＮ− （
ｍ−ヒドロキシフェニル）マレイミドを含有する超臨界
状態の二酸化炭素を抜き□出し、セパレーターで常温、
大気圧とし二酸化炭素と抽出物２８．８Ｑとに分離した
。Example 4 N-(m-hydroxyphenyl)maleimide 82% by weight
and its (l!!18[it% composition of yellow-brown N-
Crude product of (m-hydroxyphenyl)maleimide 40.
Charge OQ into a 0.31 stainless steel pressure container, supply carbon dioxide from the gas inlet, and while maintaining the inside of the stainless steel pressure container at a temperature of 60°C and a pressure of 250 and 9/ctiG, open one gas outlet. Continuously from N- (
Supercritical carbon dioxide containing m-hydroxyphenyl)maleimide is extracted and heated at room temperature in a separator.
It was brought to atmospheric pressure and separated into carbon dioxide and extract 28.8Q.
（ｑられた抽出物は黄色結晶であり、その組成はＮ−（
ｍ−ヒドロキシフェニル）マレイミドが９７重量％であ
った。(The extracted extract is yellow crystals, whose composition is N-(
m-hydroxyphenyl)maleimide was 97% by weight.
実施例 ５
Ｎ− （ｐ−メチルフェニル）マレイミド８６重量％お
よびその他１４重量％の組成の黄褐色のＮ−（ｐ−メチ
ルフェニル）マレイミドの粗製物４０、Ｏｑを０．３１
のステンレス製耐圧容器に仕込み、ガス吹き込み口より
、二酸化炭素を供給し、ステンレス製耐圧容器内を温度
５０℃、圧力２００ Ｋｇ／ ｃｉ Ｇに保ちな
がら、一方のガス抜き出し口から連続的にＮ−（ｐ−メ
チルフェニル）マレイミドを含有する超臨界状態の二酸
化炭素を扱き出し、セパレーターで常温、大気圧とし二
酸化炭素と抽出物３２．１９とに分離した。Example 5 40 crude product of yellowish brown N-(p-methylphenyl)maleimide having a composition of 86% by weight of N-(p-methylphenyl)maleimide and 14% by weight of others, Oq 0.31
Carbon dioxide was supplied from the gas inlet, and while maintaining the inside of the stainless steel pressure container at a temperature of 50°C and a pressure of 200 Kg/ci G, N- was continuously supplied from one gas outlet. Supercritical carbon dioxide containing (p-methylphenyl)maleimide was taken out and separated into carbon dioxide and extract 32.19 using a separator at room temperature and atmospheric pressure.
得られた抽出物は黄白色結晶であり、その組成はＮ−
（ｐ−メチルフェニル）マレイミドが９８重量％であっ
た。The obtained extract is yellowish white crystals, the composition of which is N-
(p-methylphenyl)maleimide was 98% by weight.
実施例 ６
Ｎ− （ｐ−ブチルフェニル）マレイミド８３重ａ％お
よびその他１７重倒％の組成の淡黄褐色のＮ− （ｐ−
ブチルフェニル）マレイミドの粗製物４０、０ＣＩを０
．３１のステンレス製耐圧容器に仕込み、ガス吹き込み
口より、二酸化炭素を供給し、ステンレス製耐圧容器内
を温度６０℃、圧力２００ Ｋｇ／ ｃｉ Ｇに保ちな
がら、一方のガス扱き出し口から連続的にＮ− （ｐ−
ブチルフェニル）マレイミドを含有する超臨界状態の二
酸化炭素を抜き出し、セパレーターで常温、大気圧とし
二酸化炭素と抽出物３０．２ｇとに分離した。Example 6 Light yellowish brown N- (p-
Butylphenyl)maleimide crude product 40, 0 CI 0
．． Carbon dioxide was supplied from the gas inlet, and while maintaining the inside of the stainless steel pressure container at a temperature of 60°C and a pressure of 200 Kg/ci G, it was continuously supplied from one gas outlet. N- (p-
Supercritical carbon dioxide containing (butylphenyl)maleimide was extracted and separated into carbon dioxide and 30.2 g of extract at room temperature and atmospheric pressure using a separator.
得られた抽出物は淡黄色結晶であり、その組成はＮ−
（ｐ−ブチルフェニル）マレイミドが９６重量％であっ
た。The obtained extract is pale yellow crystals, the composition of which is N-
(p-butylphenyl)maleimide was 96% by weight.
実施例 ７
Ｎ−（ｏ−メトキシフェニル）マレイミド８２重ａ％お
よびその他１８重量％の組成の淡黄褐色のＮ−（○ーメ
トキシフェニル）マレイミドの粗製物４０．０ｇを０．
３１のステンレス製耐圧容器に仕込み、ガス吹き込み口
より、二酸化炭素を供給し、ステンレス製耐圧容器内を
温度５０℃、圧力２ ０ ０ Ｋｇ／ ｃｍ Ｇに保ち
ながら、一方のガス扱き出し口から連続的にＮ−（０−
メトキシフェニル）マレイミドを含有する超臨界状態の
二酸化炭素を央き出し、セパレーターで常温、大気圧と
し二酸化炭素と抽出物３０．５ｇとに分離した。Example 7 40.0 g of a pale yellow-brown crude product of N-(o-methoxyphenyl)maleimide having a composition of 82% by weight of N-(o-methoxyphenyl)maleimide and 18% by weight of others was added to 0.0g of crude product of N-(○-methoxyphenyl)maleimide.
Carbon dioxide was supplied from the gas inlet, and while maintaining the temperature inside the stainless steel pressure vessel at 50°C and the pressure at 200 Kg/cm G, it was continuously supplied from one gas outlet. Generally N-(0-
Carbon dioxide in a supercritical state containing methoxyphenylmaleimide was taken out from the center and separated into carbon dioxide and 30.5 g of extract at room temperature and atmospheric pressure using a separator.
得られた抽出物は淡黄色結晶であり、その組成はＮ−（
０−メトキシフェニル）マレイミドが９７重借％であっ
た。The obtained extract is a pale yellow crystal with a composition of N-(
0-methoxyphenyl)maleimide was 97%.
実施例 ８
Ｎ−（ｐ−ブトキシフェニル）マレイミド８０千債％お
よびその他２０重最％の組成の淡黄褐色のＮ−（Ｃ）−
ブトキシフェニル）マレイミドの粗ｉＪ物４０．ＱＣ）
を０．３ｊ！のステンレス製耐圧容器に仕込み、ガス吹
き込み口より、二酸化炭素を供給し、ステンレス製耐圧
容器内を温度６０℃、圧力２００ Ｋ’Ｊ ／ ｃｉ
Ｇに保ちながら、一方のガス扱き出し口から連続的にＮ
−（ｐ−ブトキシフェニル）マレイミドを含有する超臨
界状態の二酸化炭素を央き出し、セパレーターで常温、
大気圧とし二酸化炭素と抽出物２９．８ｇとに分離した
。Example 8 Pale yellowish brown N-(C)- with a composition of 80,000% N-(p-butoxyphenyl)maleimide and 20% other by weight.
Crude iJ product of butoxyphenyl)maleimide 40. QC)
0.3j! Carbon dioxide is supplied from the gas inlet, and the temperature inside the stainless steel pressure container is kept at 60℃ and the pressure is 200 K'J/ci.
Continuously apply N from one gas outlet while maintaining the
- Carbon dioxide in a supercritical state containing (p-butoxyphenyl)maleimide is extracted from the center, and heated at room temperature with a separator.
The pressure was set to atmospheric pressure and carbon dioxide and 29.8 g of extract were separated.
得られた抽出物は淡黄色結晶であり、その組成はＮ−（
ｐ−ブトキシフェニル）マレイミドが９６重堡％であっ
た。The obtained extract is a pale yellow crystal with a composition of N-(
p-butoxyphenyl)maleimide was 96% by weight.
（発明の効果）
本発明によれば、フェニルマレイミド類粗製物に超臨界
二酸化炭素を作用させることによって、フェニルマレイ
ミド類の純度・品質の良好なものをしかも収率よ＜ Ｉ
Ｎることかできる。(Effects of the Invention) According to the present invention, phenylmaleimides with good purity and quality can be obtained by treating the crude phenylmaleimide with supercritical carbon dioxide, and in a yield of <I
I can do N.
従来、沸点が高く蒸留できなかったものや、再結晶力で
の残存溶媒の除去を必要とする製品は純度および収率が
低く、あるいは事実上、工業的に精製品が得られなかっ
た。これに対して本発明では、十分に工業的規模で、純
度９５重量％以上のフェニルマレイミド類が得られる効
果を有するものである。Conventionally, products with high boiling points that could not be distilled or products that required removal of residual solvent by recrystallization had low purity and yield, or in fact, purified products could not be obtained industrially. In contrast, the present invention has the effect of obtaining phenylmaleimides with a purity of 95% by weight or more on a sufficiently industrial scale.
特許出願人 日本触媒化学工業株式会社手 続
補 正 書 く自発〉昭和６１年Ｚ月３ 日Patent applicant Nippon Shokubai Chemical Co., Ltd. Procedures
Amendment Voluntary Letter, Z.3, 1986
Claims (3)
キシル基、炭素数１〜６のアルキル基または炭素数１〜
６のアルコキシ基を示す。〕 で示されるフェニルマレイミド類の粗製物に超臨界状態
の二酸化炭素を接触させて得られる、フェニルマレイミ
ド類を含有する二酸化炭素からフェニルマレイミド類を
分離回収することを特徴とするフェニルマレイミド類の
精製方法。(1) General formula (1) ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(1) [In the formula, R is hydrogen, halogen, carboxyl group, hydroxyl group, alkyl group having 1 to 6 carbon atoms, or 1 carbon number ~
6 shows an alkoxy group. ] Purification of phenylmaleimides, characterized by separating and recovering phenylmaleimides from carbon dioxide containing phenylmaleimides, which is obtained by contacting the crude product of phenylmaleimides represented by supercritical carbon dioxide with carbon dioxide containing phenylmaleimides. Method.
０℃、圧力が７４．２〜５００Ｋｇ／ｃｍ＾２Ｇの範囲
であることを特徴とする特許請求の範囲第１項の精製方
法。(2) Supercritical carbon dioxide has a temperature of 31.1°C to 20°C
The purification method according to claim 1, characterized in that the temperature is 0° C. and the pressure is in the range of 74.2 to 500 Kg/cm^2G.
圧力７５〜３００Ｋｇ／ｃｍ＾２Ｇの範囲であることを
特徴とする特許請求の範囲第１項の精製方法。(3) Carbon dioxide in a supercritical state has a temperature of 40 to 140°C,
The purification method according to claim 1, characterized in that the pressure is in the range of 75 to 300 kg/cm^2G.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61183352A JPS6339858A (en) | 1986-08-06 | 1986-08-06 | Purification of phenylmaleimide |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61183352A JPS6339858A (en) | 1986-08-06 | 1986-08-06 | Purification of phenylmaleimide |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6339858A true JPS6339858A (en) | 1988-02-20 |
Family
ID=16134237
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61183352A Pending JPS6339858A (en) | 1986-08-06 | 1986-08-06 | Purification of phenylmaleimide |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6339858A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2018155880A (en) * | 2017-03-16 | 2018-10-04 | 保土谷化学工業株式会社 | Charge control agents and toners using imidobenzoic acid derivatives |
-
1986
- 1986-08-06 JP JP61183352A patent/JPS6339858A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2018155880A (en) * | 2017-03-16 | 2018-10-04 | 保土谷化学工業株式会社 | Charge control agents and toners using imidobenzoic acid derivatives |
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