CN114956985B - Method for preparing 2, 5-dihydroxyterephthalic acid by oxygen oxidation - Google Patents
Method for preparing 2, 5-dihydroxyterephthalic acid by oxygen oxidation Download PDFInfo
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- CN114956985B CN114956985B CN202210667858.8A CN202210667858A CN114956985B CN 114956985 B CN114956985 B CN 114956985B CN 202210667858 A CN202210667858 A CN 202210667858A CN 114956985 B CN114956985 B CN 114956985B
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- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/41—Preparation of salts of carboxylic acids
- C07C51/412—Preparation of salts of carboxylic acids by conversion of the acids, their salts, esters or anhydrides with the same carboxylic acid part
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
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- C07C51/02—Preparation of carboxylic acids or their salts, halides or anhydrides from salts of carboxylic acids
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Abstract
The invention discloses a method for preparing 2, 5-dihydroxyterephthalic acid by oxygen oxidation, which is to oxidize succinyl succinic acid dialkyl ester to prepare 2, 5-dihydroxyterephthalic acid by oxygen-containing gas under alkaline conditions, and has the advantages of cheap and easily obtained raw materials, high safety of the reaction process, few and simple operation steps and good application prospect without adding other catalysts.
Description
Technical Field
The invention belongs to the field of organic synthesis, and particularly relates to synthesis of organic aromatic diacid, in particular to a preparation method of 2, 5-dihydroxyterephthalic acid.
Background
2, 5-dihydroxyterephthalic acid (DHTA) is an important chemical raw material, can be used for synthesizing medicines, energy materials, luminescent materials and high-performance polymer materials (chemistry and adhesion, 2015,37 (6), 451), and has important application value.
The preparation method mainly comprises the following four steps:
1. hydroquinone is used as a raw material, carbon dioxide is introduced under the strong alkaline condition, and a specific catalyst is adopted to carry out Kelbe-Schmitt (Kolbe-Schmitt) reaction to prepare (CN 10158642A; EP2530067A1; chemical and adhesive 2007,29 (6), 413; chemical and adhesive 2021,43 (6), 432). However, the reaction needs to be carried out at high temperature and high pressure, and has certain safety hazards.
2. In the presence of copper catalyst, p-xylene is used as raw material to obtain DHTA (CN 104829449A) through oxidation reaction. However, the introduction of the copper catalyst can lead to copper ions in the product, and the transition metal ion residue affects the quality of the DHTA product, so that the application range of the DHTA product is limited.
3. Under certain conditions, 2, 5-dihaloterephthalic acid or aminoterephthalic acid is hydrolyzed to prepare DHTA. However, the cost of 2, 5-dihalogenated terephthalic acid is high, and the method has no practical application value.
4. Dimethyl succinyl succinate is used as a raw material, iodine or quinone is used as a catalyst, and hydrogen peroxide is used for oxidation under the heating condition to prepare DHTA (university of Jilin university report (natural science edition), 2013,34 (4), 8; CN112624915A). However, the method involves high-temperature use of hydrogen peroxide and has considerable potential safety hazard.
In summary, the above preparation method has some practical problems in terms of safety and practicality, and the lack of a simple preparation method of DHTA limits the scale application of the product to a certain extent.
Disclosure of Invention
The invention aims to overcome the problems in the prior art and provide an economical, safe and practical method for preparing 2, 5-dihydroxyterephthalic acid by oxidizing dialkyl succinyl succinate serving as a raw material by adopting gas containing oxygen. According to the method, water is used as a main solvent, other extra catalysts are not added under an alkaline condition, and the succinyl succinic acid dialkyl ester can be directly oxidized and hydrolyzed under a heating condition by adopting air or oxygen, so that the 2, 5-dihydroxyterephthalic acid is generated by one-pot reaction. The method is carried out under normal pressure, has simple reaction steps, uses the raw materials which are economical and have little hazard, greatly improves the preparation conditions and has good industrialized prospect.
The technical proposal of the invention
The method for preparing 2, 5-dihydroxyterephthalic acid by oxygen oxidation mainly comprises the following steps: the method comprises the steps of oxidizing the dialkyl succinyl succinate by using water or a mixed solution of water and an organic solvent as a solvent medium in the presence of an alkaline substance and using a gas containing oxygen, then adding an aqueous solution of a reducing agent, and adding an acidic substance for acidification to obtain the 2, 5-dihydroxyterephthalic acid.
The synthetic route is as follows:
the specific preparation process is as follows:
adding succinyl succinic acid dialkyl ester, alkaline substances and solvent (water or mixed solution of water and organic solvent) into a reaction tank provided with a stirring, temperature controlling and condensing device, introducing gas containing oxygen, stirring and heating for a period of time, cooling and adding aqueous solution of reducing agent, adding acidic substances into the reactor to neutralize pH between 2 and 4, cooling and filtering, washing and drying a filter cake to obtain a target product, wherein the reaction yield is more than 80 percent.
Wherein the aqueous reducing agent solution may remove a small amount of the over-oxidized product.
Preferably, the molar ratio of the dialkyl succinyl succinate to the alkaline substance is 1: (2-8), the mass ratio of the dialkyl succinyl succinate to the water is 1: (2-10), the mass ratio of water to organic solvent is 1: (0-2), the reaction temperature is 40-130 ℃, the reaction time is between 2-72 hours according to the different added raw material amounts, and the mass ratio of the dialkyl succinyl succinate to the aqueous solution of the reducing agent is 1: (0.01-0.1).
Preferably, the alkyl group in the raw material dialkyl succinyl succinate is a C1-C8 substituted alkyl group such as methyl, ethyl, propyl, etc.
In a further preferred embodiment, the starting material used is dimethyl succinyl succinate.
Preferably, the organic solvent is C1-C4 fatty alcohol, tetrahydrofuran, methyltetrahydrofuran, acetone, butanone, 1, 4-dioxane, acetonitrile, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide or other water-miscible organic solvents.
Preferably, the alkaline substance is sodium carbonate, potassium carbonate, cesium carbonate, sodium hydroxide, potassium hydroxide, cesium hydroxide, or tetraalkylammonium hydroxide (R 1 R 2 R 3 R 4 )N + OH - Wherein R is 1 、R 2 、R 3 、R 4 Each independently selected from one of C1-C20 alkyl groups.
Preferably, the mixed gas containing oxygen is at least one of oxygen and nitrogen, argon, carbon dioxide or air, wherein the volume concentration of the oxygen is 5% -100%.
In a further preferred embodiment, the oxygen-containing gas used is pure oxygen.
Preferably, the aqueous solution of the reducing agent is selected from at least one of sodium sulfite solution, sodium bisulfite solution, sodium thiosulfate solution, sodium dithionite solution, hydrazine hydrate, hydroxylamine solution, hypophosphorous acid solution or phosphorous acid solution, and preferably, the mass fraction of the reducing agent in the aqueous solution of the reducing agent is 10-80 wt%.
Preferably, the acidic substance is sulfuric acid, hydrochloric acid or phosphoric acid.
The endpoints of the ranges and any values disclosed in the present invention are not limited to the precise range or value, and the range or value should be understood to include values close to the range or value. For numerical ranges, one or more new numerical ranges may be obtained in combination with each other between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point values, and are to be considered as specifically disclosed in the present invention. The technical solutions in the following embodiments can in principle be combined with one another to give new technical solutions, which should also be regarded as specifically disclosed in the present invention.
The invention has the advantages and beneficial effects that:
the invention prepares the 2, 5-dihydroxyterephthalic acid by oxidizing the dialkyl succinyl succinate with the gas containing oxygen under alkaline condition, has cheap and easily obtained reaction raw materials, high safety of the reaction process, few and simple operation steps and good application prospect.
Drawings
FIG. 1 shows a schematic representation of the chemical reaction process of the method of the present invention;
FIG. 2 shows a nuclear magnetic resonance hydrogen spectrum of 2, 5-dihydroxyterephthalic acid prepared in example 1 of the present invention.
Detailed Description
The invention is described in detail below with reference to the drawings and the specific embodiments, it is necessary to point out that the following embodiments are only for further description of the invention and are not to be construed as limiting the scope of the invention, and some insubstantial modifications and adaptations of the invention by those skilled in the art based on the present disclosure remain within the scope of the invention.
In addition, the specific features described in the following embodiments may be combined in any suitable manner without contradiction. The various possible combinations of the invention are not described in detail in order to avoid unnecessary repetition.
In addition, any combination of the various embodiments of the present invention can be made, so long as the concept of the present invention is not deviated, and the technical solution formed thereby is a part of the original disclosure of the present specification, and also falls within the protection scope of the present invention.
The starting materials employed in the examples, if not particularly limited, are all those disclosed in the prior art, and are, for example, available directly or prepared according to the preparation methods disclosed in the prior art.
[ example 1 ]
The reaction route of the 2, 5-dihydroxyterephthalic acid prepared by oxygen oxidation is shown in figure 1.
11.4kg of dimethyl succinyl succinate, 16kg of sodium hydroxide (namely, the molar ratio of the dimethyl succinyl succinate to the sodium hydroxide is 1:8) and 22.8kg of pure water solution are added into a reaction tank provided with a stirring, temperature controlling and condensing device, pure oxygen is introduced, the mixture is stirred and heated to 130 ℃, the reaction is carried out for 72 hours, 0.12kg of 80% hydrazine hydrate solution is added after cooling, 1mol/L sulfuric acid is added for neutralization pH value is 3.0, cooling and filtering are carried out, and 9.0kg of yellow powdery solid obtained after a filter cake is washed and dried is 2, 5-dihydroxyterephthalic acid, and the yield is 91%.
5mg of 2, 5-dihydroxyterephthalic acid sample is dissolved in 0.5mL of dimethyl sulfoxide and is uniformly dispersed by ultrasonic, and a Fourier nuclear magnetic resonance spectrometer is adopted for testing to obtain the figure 2.
[ example 2 ]
2, 5-dihydroxyterephthalic acid is prepared by oxygen oxidation, 1.28kg of diethyl succinyl succinate, 1.96kg of potassium hydroxide (namely, the molar ratio of dimethyl succinyl succinate to sodium hydroxide is 1:7) and 3.84kg of water are added into a reaction tank provided with a stirring, temperature-reducing and condensing device, 0.768kg of organic solvent is added, 90% of oxygen and 10% of argon mixed gas are introduced into the reaction tank, the reaction tank is stirred and heated to 110 ℃, the temperature is reduced and 80% of hydrazine hydrate solution is added for 0.026kg, then 1mol/L hydrochloric acid is added for neutralizing the pH to be 3.0, the reaction tank is cooled and filtered, and the yellow powdery solid obtained after the filter cake is washed and dried is 0.88kg of 2, 5-dihydroxyterephthalic acid, and the yield is 89%.
[ example 3 ]
2, 5-dihydroxyterephthalic acid is prepared by oxygen oxidation, 1.42kg of succinyl succinic acid dipropyl ester, 1.2kg of sodium hydroxide (namely, the molar ratio of the succinyl succinic acid dimethyl ester to the sodium hydroxide is 1:6) and 5.68kg of water are added into a reaction tank provided with a stirring and cooling and condensing device, 2.84kg of organic solvent, mixed gas of 80% of oxygen and 20% of nitrogen is introduced into the reaction tank, the reaction tank is stirred and heated to 100 ℃, the temperature is reduced, 0.043kg of 80% hydrazine hydrate solution is added, 1mol/L phosphoric acid is added to neutralize the pH to 3.0, the reaction tank is cooled and filtered, and 0.87kg of yellow powdery solid of a filter cake after washing and drying is 2, 5-dihydroxyterephthalic acid, and the yield is 88%.
[ example 4 ]
2, 5-dihydroxyterephthalic acid is prepared by oxygen oxidation, 1.56kg of dibutyl succinyl succinate, 1.4kg of potassium hydroxide (namely, the molar ratio of dimethyl succinyl succinate to sodium hydroxide is 1:5) and 7.8kg of water are added into a reaction tank provided with a stirring, temperature-reducing and condensing device, 6.24kg of organic solvent, 60% of oxygen and 40% of carbon dioxide mixed gas are introduced, the mixture is stirred and heated to 90 ℃, reaction is carried out for 40 hours, 80% of hydrazine hydrate solution is cooled and added for 0.078kg, 1mol/L sulfuric acid is then added for neutralizing pH to 3.0, cooling and filtering are carried out, and 0.85kg of yellow powdery solid obtained after filter cake is washed and dried is 2, 5-dihydroxyterephthalic acid, and the yield is 86%.
[ example 5 ]
2, 5-dihydroxyterephthalic acid is prepared by oxygen oxidation, 1.70kg of dipentyl succinyl succinate, 0.8kg of sodium hydroxide (namely, the molar ratio of dimethyl succinyl succinate to sodium hydroxide is 1:4) and 10.2kg of water are added into a reaction tank provided with stirring and temperature-reducing condensing devices, 10.2kg of organic solvent is added, mixed gas of 40% of oxygen and 60% of argon is introduced into the reaction tank, the reaction tank is stirred and heated to 80 ℃, the temperature is reduced, 0.102kg of 80% hydrazine hydrate solution is added, then 1mol/L sulfuric acid is added for neutralizing the pH to be 3.0, the reaction tank is cooled and filtered, and 0.84kg of yellow powdery solid obtained after filter cake is washed and dried is 2, 5-dihydroxyterephthalic acid, and the yield is 85%.
[ example 6 ]
2, 5-dihydroxyterephthalic acid is prepared by oxygen oxidation, 1.84kg of dihexyl succinyl succinate, 0.84kg of potassium hydroxide (namely, the molar ratio of dimethyl succinyl succinate to sodium hydroxide is 1:3) and 14.7kg of water are added into a reaction tank provided with a stirring, temperature-reducing and condensing device, 17.7kg of organic solvent, mixed gas of 20% of oxygen and 80% of carbon dioxide is introduced into the reaction tank, the reaction tank is stirred and heated to 70 ℃, the temperature is reduced, 0.147kg of 80% hydrazine hydrate solution is added, then 1mol/L hydrochloric acid is added for neutralizing the pH to be 3.0, the reaction tank is cooled and filtered, and 0.82kg of yellow powdery solid obtained after the filter cake is washed and dried is 2, 5-dihydroxyterephthalic acid, and the yield is 83%.
[ example 7 ]
2, 5-dihydroxyterephthalic acid is prepared by oxygen oxidation, 1.98kg of succinyl succinic acid diheptyl ester, 0.56kg of potassium hydroxide (namely, the molar ratio of dimethyl succinyl succinate to sodium hydroxide is 1:2) and 17.8kg of water are added into a reaction tank provided with a stirring and cooling and condensing device, 26.7kg of organic solvent, mixed gas of 10% of oxygen and 90% of carbon dioxide is introduced into the reaction tank, the reaction tank is stirred and heated to 60 ℃, the temperature is reduced, 0.178kg of 80% hydrazine hydrate solution is added, then 1mol/L hydrochloric acid is added for neutralizing the pH to be 3.0, the reaction tank is cooled and filtered, and 0.81kg of yellow powdery solid obtained after the filter cake is washed and dried is 2, 5-dihydroxyterephthalic acid, and the yield is 82%.
[ example 8 ]
2, 5-dihydroxyterephthalic acid is prepared by oxygen oxidation, 2.12kg of dioctyl succinyl succinate, 0.2kg of sodium hydroxide (namely, the molar ratio of dimethyl succinyl succinate to sodium hydroxide is 1:1) and 21.2kg of water are added into a reaction tank provided with a stirring, temperature-reducing and condensing device, 42.4kg of organic solvent is added, mixed gas of 5% of oxygen and 95% of air is introduced into the reaction tank, the reaction tank is stirred and heated to 40 ℃, the temperature is reduced, 0.212kg of 80% hydrazine hydrate solution is added, 1mol/L hydrochloric acid is added to neutralize the pH to 3.0, the reaction tank is cooled and filtered, and 0.79kg of yellow powdery solid after filter cake is washed and dried is 2, 5-dihydroxyterephthalic acid, and the yield is 80%.
The invention has been described in detail in connection with the specific embodiments and exemplary examples thereof, but such description is not to be construed as limiting the invention. It will be understood by those skilled in the art that various equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its embodiments without departing from the spirit and scope of the present invention, and these fall within the scope of the present invention. The scope of the invention is defined by the appended claims.
Claims (6)
1. A process for preparing 2, 5-dihydroxyterephthalic acid by oxygen oxidation comprising:
(1) Oxidizing the dialkyl succinyl succinate by using water or a mixed solution of water and an organic solvent as a solvent medium in the presence of potassium hydroxide or sodium hydroxide and adopting gas containing oxygen; the dialkyl succinyl succinate is dimethyl succinyl succinate, diethyl succinyl succinate, dipropyl succinyl succinate, dibutyl succinyl succinate, dipentyl succinyl succinate, dihexyl succinyl succinate, diheptyl succinyl succinate or dioctyl succinyl succinate;
(2) Adding hydrazine hydrate aqueous solution after the reaction is finished;
(3) Adding acidic substances to acidify to obtain the 2, 5-dihydroxyterephthalic acid.
2. The method according to claim 1, wherein the organic solvent is a C1-C4 aliphatic alcohol, tetrahydrofuran, methyltetrahydrofuran, acetone, butanone, 1, 4-dioxane, acetonitrile, N-dimethylformamide, N-dimethylacetamide, dimethylsulfoxide, or other water-miscible organic solvents.
3. The method of claim 1, wherein the oxygen-containing gas mixture is at least one of oxygen and nitrogen, argon, carbon dioxide, or air, wherein the oxygen is present in a concentration of 5% to 100% by volume.
4. The method of claim 1, wherein the acidic material is sulfuric acid, hydrochloric acid, or phosphoric acid.
5. The method according to any one of claims 1 to 4, wherein the method is specifically prepared by: adding succinyl succinic acid dialkyl ester, potassium hydroxide or sodium hydroxide and a solvent into a reaction tank provided with a stirring, temperature controlling and condensing device, introducing oxygen-containing gas, stirring and heating, cooling, adding hydrazine hydrate aqueous solution, adding acidic substances into a reactor to neutralize pH between 2 and 4, cooling and filtering, washing and drying a filter cake to obtain a target product, wherein the reaction yield is more than 80 percent; wherein an aqueous solution of the reducing agent is used to remove small amounts of the over-oxidized product.
6. The method of claim 5, wherein the molar ratio of the dialkyl succinyl succinate to potassium hydroxide or sodium hydroxide is 1: (2-8), the mass ratio of the dialkyl succinyl succinate to the water is 1: (2-10), the mass ratio of water to organic solvent is 1: (0-2), the reaction temperature is 40-130 ℃, the reaction time is between 2-72 hours according to the different added raw material amounts, and the mass ratio of the dialkyl succinyl succinate to the hydrazine hydrate aqueous solution is 1: (0.01-0.1);
the reaction route is as follows:
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1469480A (en) * | 1964-09-02 | 1967-02-17 | Alpine Chemische Ag | Manufacturing process of 2.5-dihydroxy terephthalic acid |
| US3448145A (en) * | 1964-09-02 | 1969-06-03 | Alpine Chemische Ag | Process for the production of 2,5-dihydroxyterephthalic acid |
| CN104829449A (en) * | 2015-05-12 | 2015-08-12 | 云南大学 | New method for synthesizing 2,5-dihydroxyterephthalic acid |
| CN112126205A (en) * | 2020-10-12 | 2020-12-25 | 宁波聚嘉新材料科技有限公司 | Preparation method of high-performance thermotropic liquid crystal polyarylate |
| CN112624915A (en) * | 2020-12-31 | 2021-04-09 | 杭州百合科莱恩颜料有限公司 | Method for preparing 2, 5-dihydroxyterephthalic acid (DHTA) |
| CN114478243A (en) * | 2022-02-24 | 2022-05-13 | 常州大学 | Method for synthesizing dihydroxy dimethyl terephthalate by oxygen catalytic oxidation method |
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Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1469480A (en) * | 1964-09-02 | 1967-02-17 | Alpine Chemische Ag | Manufacturing process of 2.5-dihydroxy terephthalic acid |
| US3448145A (en) * | 1964-09-02 | 1969-06-03 | Alpine Chemische Ag | Process for the production of 2,5-dihydroxyterephthalic acid |
| CN104829449A (en) * | 2015-05-12 | 2015-08-12 | 云南大学 | New method for synthesizing 2,5-dihydroxyterephthalic acid |
| CN112126205A (en) * | 2020-10-12 | 2020-12-25 | 宁波聚嘉新材料科技有限公司 | Preparation method of high-performance thermotropic liquid crystal polyarylate |
| CN112624915A (en) * | 2020-12-31 | 2021-04-09 | 杭州百合科莱恩颜料有限公司 | Method for preparing 2, 5-dihydroxyterephthalic acid (DHTA) |
| CN114478243A (en) * | 2022-02-24 | 2022-05-13 | 常州大学 | Method for synthesizing dihydroxy dimethyl terephthalate by oxygen catalytic oxidation method |
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