CN111116435A - Refining method of 4, 4' -bis (3-aminophenoxy) diphenyl sulfone - Google Patents
Refining method of 4, 4' -bis (3-aminophenoxy) diphenyl sulfone Download PDFInfo
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- CN111116435A CN111116435A CN201911201309.6A CN201911201309A CN111116435A CN 111116435 A CN111116435 A CN 111116435A CN 201911201309 A CN201911201309 A CN 201911201309A CN 111116435 A CN111116435 A CN 111116435A
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- C07—ORGANIC CHEMISTRY
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- C07C315/00—Preparation of sulfones; Preparation of sulfoxides
- C07C315/06—Separation; Purification; Stabilisation; Use of additives
Abstract
A refining method of 4, 4' -bis (3-aminophenoxy) diphenyl sulfone comprises the following steps: s1: adding the crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into a solvent, heating to a first temperature, dissolving and clarifying to obtain a solution; s2: primarily filtering the solution obtained in the step S1; s3: cooling the solution obtained in the step S2, and then carrying out secondary filtration; s4: and drying the filtered product to obtain the 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product. The solvent is one or two of trichloromethane and acetonitrile. The two solvents may be used alone or in combination. Compared with the traditional refining method, the refining method has the advantages that the organic solvent is replaced by one or two of trichloromethane and acetonitrile, the yield and the purity of the refined product are high, and the quality of the refined product is improved; the method has better industrial application prospect.
Description
Technical Field
The invention relates to a refining method of chemical products, in particular to a refining method of 4, 4' -bis (3-aminophenoxy) diphenyl sulfone.
Background
4, 4' -bis (3-aminophenoxy) diphenyl sulfone is a novel amine compound, can be used as an amine curing agent of epoxy resin to improve the performance of the epoxy resin, can be used as a synthetic raw material of polyimide and other high polymers, and has wide application in high polymer materials.
Because 4,4 '-bis (3-aminophenoxy) diphenyl sulfone is a raw material for preparing a high polymer material, the quality of the 4, 4' -bis (3-aminophenoxy) diphenyl sulfone has to influence the performance of the high polymer material and can meet the use requirement only by refining. The existing refining method of 4, 4' -bis (3-aminophenoxy) diphenyl sulfone comprises a hydrochloric acid and sodium hydroxide solution refining method. "Synthesis of 4, 4' -bis (3-aminophenoxy) diphenylsulfone, chemical and adhesion, 1998, No. 4" discloses purification by the hydrochloride salt method. Reacting crude m-BAPS with hydrochloric acid (the molar ratio of m-BAPS to HCl is 1.0: 1.0-5.0), heating to dissolve, hot filtering, cooling the solution, precipitating hydrochloride of m-BAPS, neutralizing with NaOH aqueous solution, precipitating m-BAPS, filtering, and drying to obtain the refined product. However, this method often results in an unsatisfactory purity. In addition, alcohol purification methods are available, but alcohol is often easily precipitated during the hot filtration process of alcohol purification, which results in blockage of pipelines, unsatisfactory yield and purity, and the need for multiple purifications.
Disclosure of Invention
The invention aims to provide a refining method of 4, 4' -bis (3-aminophenoxy) diphenyl sulfone, namely a new crystallization solvent is selected, the solvent can be randomly filtered after being heated, dissolved and clarified, the phenomenon that the solvent is separated out after being slightly cooled does not exist, the problem of pipeline blockage (namely blockage of a sieve pore or filter paper for filtering) can be avoided, in addition, the solvent has higher purification efficiency, higher purity can be achieved once, the yield is higher, and the method has good industrial prospect.
A refining method of 4, 4' -bis (3-aminophenoxy) diphenyl sulfone comprises the following steps:
s1: adding the crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into a solvent, heating to a first temperature, dissolving and clarifying to obtain a solution;
s2: primarily filtering the solution obtained in the step S1;
s3: cooling the solution obtained in the step S2, and then carrying out secondary filtration;
s4: and drying the filtered product to obtain the 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product.
Further, in step S1, the solvent is one or two of chloroform and acetonitrile. The two solvents may be used alone or in combination.
Further, the solvent is acetonitrile.
Further, in step S1, the mass of the solvent is 2 to 5 times of the mass of the crude 4, 4' -bis (3-aminophenoxy) diphenylsulfone.
Further preferably, the mass of the solvent is 3-4 times of that of the crude product of the 4, 4' -bis (3-aminophenoxy) diphenyl sulfone;
the solvent amount is too low, which results in incomplete dissolution and low efficiency. Too large amount of solvent results in less precipitation during cooling and too low product yield.
Further, in step S1, the heating method may be a conventional heating method in the prior art, such as heat medium heating, electric heating, microwave heating, and the like, and preferably a heating method with better heating speed and temperature controllability, such as hot water and hot oil heating.
Further, after the dissolution clarification in the step S1, the solution is kept at a temperature for a certain period of time to ensure the dissolution effect.
The heat preservation time in the step S1 is preferably 5-120 min.
Further preferably, the temperature is kept for 10-40 min. Too long a heat preservation time will result in too long a production flow and reduced production efficiency.
Further, the process of S1 includes stirring. The dissolution rate can be effectively improved by adopting a stirring mode. The stirring can be performed by conventional magnetic stirring, mechanical stirring and other stirring methods. The choice of the equipment can be made in particular according to the equipment used.
Further, the first temperature in S1 is 60 to 80 ℃.
Further, the step of S2 is a hot filtration, preferably at a temperature of 60-80 ℃.
Further, the filtration in S2 adopts conventional filtration methods such as suction filtration and filter pressing.
S3: cooling the solution obtained in the step S2, standing for 1-5h, and filtering for the second time
Further, the target temperature of the temperature decrease in S3 is 0 to 15 ℃. The yield of the product can be improved at low temperature, but too low temperature leads to too high impurity content of the product, and too high temperature leads to too low yield of the product.
Further, the target temperature of the temperature decrease in S3 is preferably 5 to 10 ℃.
Furthermore, in the cooling manner in S3, cooling speed may be increased by using a cooling pipe, a cooling jacket, or the like, or temperature may be decreased by using natural cooling.
Further preferably, a natural cooling method or a cooling method with a low cooling rate is adopted. Further preferably, a cooling mode of 1-10 ℃/min is adopted.
Further, the secondary filtration mode adopts conventional filtration modes such as suction filtration, filter pressing and the like.
Further, the drying step in S4 may be performed by conventional drying methods, such as vacuum drying, freeze drying, microwave drying, etc.
Further preferably, the drying is performed by vacuum drying. The vacuum drying temperature is 20-60 ℃, and the gauge pressure is-0.01 MPa to-0.099 MPa.
Too high a vacuum drying temperature may cause adhesion of the product, and too low a temperature may cause low efficiency, and it is further preferable to use a drying temperature of 40 to 50 ℃. The higher the degree of vacuum, the higher the drying efficiency.
The invention has the beneficial effects that:
1. compared with the traditional refining method, the refining method has the advantages that the organic solvent is replaced by one or two of trichloromethane and acetonitrile, the yield and the purity of the refined product are high, and the quality of the refined product is improved;
2. the refining method has simple operation steps, reduces the refining cost and simultaneously reduces the requirements on refining operators;
3. the refining method does not cause the problem of pipeline blockage, so that the refining process can be continuously carried out, and the complicated operation of cleaning the pipeline is effectively avoided;
4. the refining method has better industrial application prospect.
Detailed Description
The crude 4,4 '-bis (3-aminophenoxy) diphenyl sulfone used in the examples of the present invention was synthesized by the method described in Liu culture, Wang Wen Bin, Zhongzang.4, 4' -bis (3-aminophenoxy) diphenyl sulfone, 1998,4(3): 209-211.
The raw materials adopted in all the embodiments of the invention are all sold in the market, the brand is Chinese medicine, and the analysis is pure.
The melting point of the invention is tested by using a JH70L microscopic digital melting point instrument.
The purity of the invention is tested by Shimadzu LC-6A High Performance Liquid Chromatography (HPLC).
The refining method of the 4, 4' -bis (3-aminophenoxy) diphenyl sulfone comprises the following steps:
s1: adding the crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into a solvent, heating to a first temperature, dissolving and clarifying to obtain a solution;
s2: primarily filtering the solution obtained in the step S1;
s3: cooling the solution obtained in the step S2, and then carrying out secondary filtration;
s4: and drying the filtered product to obtain the 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product.
The invention is further illustrated by the following examples:
example 1:
adding 100g of crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into 300g of acetonitrile solvent at normal temperature, stirring by conventional magnetic stirring, heating to 80 ℃ for dissolution and clarification, wherein the heating mode is medium heating, the medium is hot water or hot oil, keeping the temperature of the solution for 5min to ensure better dissolution effect, keeping the temperature for 30min after dissolution and clarification, filtering while hot, the filtering temperature is 78 ℃, cooling the filtrate to 5 ℃, standing for crystallization for 2.5h, and the cooling mode is natural cooling and secondary filtering. Melting point of the obtained white end product, i.e. 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product: 132 ℃ and 133 ℃, HPLC: 99.5%, yield: the yield is 90 percent, namely the mass percentage of the white finished product and the crude product.
Example 2:
adding 100g of crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into 400g of acetonitrile at normal temperature, mechanically stirring, effectively increasing the dissolution rate, heating to 75 ℃ for dissolution and clarification, wherein the heating mode is electric heating, keeping the temperature for 10min after dissolution and clarification, filtering while hot, the filtering temperature is 70 ℃, cooling the filtrate to 15 ℃, standing and crystallizing for 5h, the cooling mode is natural cooling and secondary filtering, in the embodiment, the filtration is carried out in a filter pressing mode, vacuum drying is carried out at 60 ℃ to obtain a white finished product, and the gauge pressure of vacuum drying is-0.01 MPa. Melting point of the obtained white end product, i.e. 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product: 132.5-133 ℃, HPLC: 99.6%, yield: 92 percent.
Example 3:
adding 100g of 4, 4' -bis (3-aminophenoxy) diphenyl sulfone crude product into 350g of trichloromethane at normal temperature, stirring by magnetic stirring, heating to 80 ℃ for dissolution and clarification, heating by microwave heating, keeping the temperature for 60min after dissolution and clarification, filtering while hot, cooling the filtrate to 6 ℃, standing and crystallizing for 3.5h, cooling by adopting a cooling pipe, filtering for the second time, and vacuum drying at 20 ℃ to obtain a white finished product, wherein the gauge pressure of vacuum drying is-0.099 MPa. Melting point of the obtained white end product, i.e. 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product: 132-133.5 ℃, HPLC: 99.7%, yield: 91 percent.
Example 4:
adding 100g of crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into 500g of solution at normal temperature, wherein the solution comprises 200g of acetonitrile and 300g of chloroform, mechanically stirring, heating to 70 ℃, dissolving and clarifying, keeping the temperature for 90min after dissolving and clarifying, filtering while hot, cooling the filtrate to 8 ℃, standing and crystallizing for 3h, wherein the cooling mode is cooling by adopting a cooling jacket, secondary filtering, vacuum drying at 40 ℃ to obtain a white finished product, and the gauge pressure of vacuum drying is-0.05 MPa. Melting point of the obtained white end product, i.e. 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product: 133 ℃ and 134 ℃, HPLC: 99.8%, yield: 91 percent.
Example 5:
adding 100g of crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into 200g of acetonitrile at normal temperature, heating to 60 ℃, dissolving and clarifying, keeping the temperature for 120min after dissolving and clarifying, filtering while hot, keeping the filtering temperature at 60 ℃, cooling the filtrate to 10 ℃, standing and crystallizing for 4h, wherein the cooling mode is natural cooling and cooling, secondary filtering, and vacuum drying at 50 ℃ to obtain a white finished product. Melting point of the obtained white end product, i.e. 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product: 132 ℃ and 133 ℃, HPLC: 99.7%, yield: 92 percent.
Example 6:
adding 100g of crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into 500g of acetonitrile at normal temperature, heating to 65 ℃, dissolving and clarifying, keeping the temperature for 100min after dissolving and clarifying, filtering while hot, wherein the filtering temperature is 70 ℃, cooling the filtrate to 3 ℃, standing and crystallizing for 2h, the cooling mode is natural cooling and cooling, secondary filtering, and vacuum drying at 45 ℃ to obtain a white finished product. Melting point of the obtained white end product, i.e. 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product: 133 ℃ and 134 ℃, HPLC: 99.8%, yield: 91 percent.
Example 7:
adding 100g of crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into 500g of chloroform at normal temperature, heating to 70 ℃, dissolving and clarifying, keeping the temperature for 110min after dissolving and clarifying, filtering while hot, wherein the filtering temperature is 75 ℃, cooling the filtrate to 0 ℃, standing and crystallizing for 1h, the cooling mode is natural cooling and cooling, secondary filtering, and vacuum drying at 40 ℃ to obtain a white finished product. Melting point of the obtained white end product, i.e. 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product: 132 ℃ and 133 ℃, HPLC: 99.6%, yield: 90.5 percent.
Comparative example 1:
adding 100g of crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into 500g of ethanol at normal temperature, heating to 87 ℃, dissolving and clarifying, keeping the temperature for 30min after dissolving and clarifying, filtering while hot, wherein the filtering temperature is 85 ℃, cooling the filtrate to 5 ℃, standing and crystallizing for 2h, filtering for the second time, and drying in vacuum at 50 ℃ to obtain a brown-white finished product. Melting point of the obtained white end product, i.e. 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product: 125 ℃ and 130 ℃, HPLC: 99.0%, yield: 80 percent.
Comparative example 2:
adding 100g of crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into 300g of ethanol at normal temperature, heating to 78 ℃, dissolving and clarifying, keeping the temperature for 30min after dissolving and clarifying, filtering while hot, wherein the filtering temperature is 75 ℃, cooling the filtrate to 5 ℃, standing and crystallizing for 2h, filtering for the second time, and drying in vacuum at 50 ℃ to obtain a white finished product. Melting point of the obtained white end product, i.e. 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product: 126 ℃ and 129 ℃, HPLC: 98.8%, yield: 75 percent.
Comparative example 3:
adding 100g of crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into 400g of ethanol at normal temperature, heating to 78 ℃, dissolving and clarifying, keeping the temperature for 30min after dissolving and clarifying, filtering while hot, cooling the filtrate to 5 ℃, standing and crystallizing for 2h, filtering for the second time, and drying in vacuum at 50 ℃ to obtain a white finished product. Melting point of the obtained white end product, i.e. 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product: 127 ℃ and 130 ℃, HPLC: 97.8%, yield: 82 percent.
Comparative example 4:
adding 100g of crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into 350g of ethanol at normal temperature, heating to 78 ℃, dissolving and clarifying, keeping the temperature for 30min after dissolving and clarifying, filtering while hot, cooling the filtrate to 10 ℃, standing and crystallizing for 2h, filtering for the second time, and vacuum drying at 50 ℃ to obtain a white finished product. Melting point of the obtained white end product, i.e. 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product: 126 ℃ 130 ℃, HPLC: 96.8%, yield: 83 percent.
Compared with the prior art, the method has the advantages of high product purity, high yield, easy operation and good industrial value.
Claims (10)
1. A refining method of 4, 4' -bis (3-aminophenoxy) diphenyl sulfone is characterized by comprising the following steps:
s1: adding the crude 4, 4' -bis (3-aminophenoxy) diphenyl sulfone into a solvent, heating to a first temperature, dissolving and clarifying to obtain a solution;
s2: primarily filtering the solution obtained in the step S1;
s3: cooling the solution obtained in the step S2, and then carrying out secondary filtration;
s4: and drying the filtered product to obtain the 4, 4' -bis (3-aminophenoxy) diphenyl sulfone product.
2. The method for purifying 4, 4' -bis (3-aminophenoxy) diphenylsulfone according to claim 1, wherein: in step S1, the solvent is one or two of chloroform and acetonitrile.
3. The method for purifying 4, 4' -bis (3-aminophenoxy) diphenylsulfone according to claim 1 or 2, characterized in that: in step S1, the mass of the solvent is 2 to 5 times of the mass of the crude 4, 4' -bis (3-aminophenoxy) diphenylsulfone.
4. The method for purifying 4, 4' -bis (3-aminophenoxy) diphenylsulfone according to claim 1, wherein: and (5) after the solution is dissolved and clarified in the step S1, keeping the temperature of the solution for a certain time to ensure the dissolving effect, wherein the temperature keeping time is 5-120 min.
5. The method for purifying 4, 4' -bis (3-aminophenoxy) diphenylsulfone according to claim 1, wherein: the first temperature is 60-80 ℃.
6. The method for purifying 4, 4' -bis (3-aminophenoxy) diphenylsulfone according to claim 1, wherein: step S2 adopts hot filtration, and the filtration temperature is 60-80 ℃.
7. The method for purifying 4, 4' -bis (3-aminophenoxy) diphenylsulfone according to claim 1, wherein: the target temperature of the temperature reduction in step S3 is 0 to 15 ℃.
8. The method for purifying 4, 4' -bis (3-aminophenoxy) diphenylsulfone according to claim 1, wherein: in the step S3, any one of suction filtration and pressure filtration is adopted as the secondary filtration.
9. The method for purifying 4, 4' -bis (3-aminophenoxy) diphenylsulfone according to claim 1, wherein: the drying in step S4 may be vacuum drying, freeze drying or microwave drying.
10. The method for purifying 4, 4' -bis (3-aminophenoxy) diphenylsulfone according to claim 9, wherein: the vacuum drying temperature is 20-60 ℃, and the gauge pressure is-0.01 MPa to-0.099 MPa.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113563240A (en) * | 2021-06-28 | 2021-10-29 | 常州市阳光药业有限公司 | Synthesis method of 4,4' -bis (3-aminophenoxy) diphenyl sulfone |
| CN113912522A (en) * | 2020-12-24 | 2022-01-11 | 常州市阳光药业有限公司 | Refining method of 4,4' -bis (3-aminophenoxy) diphenyl sulfone |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3988374A (en) * | 1970-06-29 | 1976-10-26 | Union Carbide Corporation | Polyamide-imides |
| US5077436A (en) * | 1985-02-22 | 1991-12-31 | Mitsui Toatsu Chemicals, Inc. | Bis(3-aminophenoxy) aromatics and method of preparing the same |
| JPH04103564A (en) * | 1990-08-24 | 1992-04-06 | Mitsui Toatsu Chem Inc | Production of bis(3-aminophenoxy) compound |
-
2019
- 2019-11-29 CN CN201911201309.6A patent/CN111116435B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3988374A (en) * | 1970-06-29 | 1976-10-26 | Union Carbide Corporation | Polyamide-imides |
| US5077436A (en) * | 1985-02-22 | 1991-12-31 | Mitsui Toatsu Chemicals, Inc. | Bis(3-aminophenoxy) aromatics and method of preparing the same |
| JPH04103564A (en) * | 1990-08-24 | 1992-04-06 | Mitsui Toatsu Chem Inc | Production of bis(3-aminophenoxy) compound |
Non-Patent Citations (6)
| Title |
|---|
| FATMA SELAMPINAR 等: "Synthesis of a Hexafluoropropylidene–Bis(phthalicanhydride)-Based Polyimide and Its Conducting Polymer Composites with Polypyrrole", 《JOURNAL OF POLYMER SCIENCE: PART A: POLYMER CHEMISTRY》 * |
| J. ADDUCI 等: "Synthesis, Characterization, and Study of Thermal Properties of Methyl-Substituted Arylene Sulfone Ether Polyimides, Polyamides, and Poly (amide-Imides)", 《JOURNAL OF APPLIED POLYMER SCIENCE》 * |
| KAZUMI SUEMATSU: "Kinetic Studies of Polyimine Formation", 《MACROMOLECULES》 * |
| LIANLAI ZHANG 等: "Preparation and Properties of Bismaleimide Resins of Aromatic Sulfone Ether Diamine", 《POLYMER INTERNATIONAL》 * |
| TOQEER KAUSAR 等: "THE SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF ARAMID-POLYDIMETHYLSILOXANE", 《MAIN GROUP METAL CHEMISTRY》 * |
| 刘培: "4,4’-双（3-氨基苯氧基）二苯砜的合成研究", 《化学与粘合》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113912522A (en) * | 2020-12-24 | 2022-01-11 | 常州市阳光药业有限公司 | Refining method of 4,4' -bis (3-aminophenoxy) diphenyl sulfone |
| CN113563240A (en) * | 2021-06-28 | 2021-10-29 | 常州市阳光药业有限公司 | Synthesis method of 4,4' -bis (3-aminophenoxy) diphenyl sulfone |
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