CN114956985A - Method for preparing 2, 5-dihydroxy terephthalic acid by oxygen oxidation - Google Patents
Method for preparing 2, 5-dihydroxy terephthalic acid by oxygen oxidation Download PDFInfo
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Abstract
The invention discloses a method for preparing 2, 5-dihydroxy terephthalic acid by oxidizing oxygen gas, which is used for preparing 2, 5-dihydroxy terephthalic acid by oxidizing dialkyl succinyl succinate under an alkaline condition, does not need to add other catalysts in the reaction, has cheap and easily obtained raw materials, high safety in the reaction process, few and simple operation steps and good application prospect.
Description
Technical Field
The invention belongs to the field of organic synthesis, particularly relates to synthesis of organic aromatic diacid, and specifically relates to a preparation method of 2, 5-dihydroxy terephthalic 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 high 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 a strong alkaline condition, and a specific catalyst is adopted to carry out a Kolbe-Schmitt (Kolbe-Schmitt) reaction to prepare the material (CN 10158642A; EP2530067A 1; chemical bonding, 2007,29(6), 413; chemical bonding, 2021,43(6), 432). However, the reaction needs to be carried out at high temperature and high pressure, and has certain safety hazards.
2. Under the condition of the existence of a copper catalyst, DHTA (CN104829449A) can be obtained by oxidation reaction of p-xylene serving as a raw material. However, the introduction of the copper catalyst can cause copper ions in the product, and the residue of the transition metal ions influences the quality of the DHTA product and limits the application range of the DHTA product.
3. DHTA is prepared by hydrolyzing 2, 5-dihaloterephthalic acid or aminoterephthalic acid under certain conditions. However, the cost of 2, 5-dihaloterephthalic acid is high, and the method has no practical application value.
4. Dimethylsuccinyl succinate is used as a raw material, iodine or quinones are used as a catalyst, and hydrogen peroxide is used for oxidation under the heating condition to prepare DHTA (proceedings of Jilin university (Nature science edition), 2013,34(4), 8; CN 112624915A). However, the method involves the high-temperature use of hydrogen peroxide and has a considerable safety hazard.
In conclusion, the preparation method has some practical problems in the aspects of safety and practicability, and the simple preparation method of DHTA is lacked, so that the large-scale application of the product is limited 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 using dialkyl succinyl succinate as a raw material and adopting gas containing oxygen for oxidation. The method takes water as a main solvent, under the alkaline condition, no other extra catalyst is added, air or oxygen is adopted under the heating condition, the succinyl succinic acid dialkyl ester can be directly oxidized and hydrolyzed, and the 2, 5-dihydroxy terephthalic acid is generated through one-pot reaction. The method is carried out under normal pressure, the reaction steps are simple, the used raw materials are economical and have small harmfulness, the preparation conditions are greatly improved, and the method has good industrial prospect.
Technical scheme of the invention
A method for preparing 2, 5-dihydroxy terephthalic acid by oxygen oxidation mainly comprises the following steps: using water or mixed solution of water and organic solvent as solvent medium, oxidizing dialkyl succinyl succinate with oxygen-containing gas in the presence of alkaline matter, adding aqueous solution of reducing agent, adding acidic matter, and acidifying to obtain 2, 5-dihydroxy terephthalic acid.
The synthetic route is as follows:
the preparation process comprises the following steps:
adding dialkyl succinyl succinate, an alkaline substance and a solvent (water or a mixed solution of water and an organic solvent) into a reaction tank provided with a stirring, temperature control and condensing device, introducing gas containing oxygen, stirring and heating for a period of time, cooling, adding a reducing agent aqueous solution, adding an acidic substance into a reactor to neutralize the pH value to be 2-4, cooling and filtering, and washing and drying a filter cake to obtain a target product, wherein the reaction yield is more than 80%.
Wherein the aqueous reducing agent solution can remove a small amount of over-oxidation products.
Preferably, the molar ratio of the dialkyl succinylsuccinate to the alkaline substance is 1: (2-8), wherein the mass ratio of the dialkyl succinyl succinate to the water is 1: (2-10), wherein the mass ratio of water to the organic solvent is 1: (0-2), the reaction temperature is 40-130 ℃, the reaction time is 2-72 hours according to the amount of the added raw materials, 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 starting dialkyl succinylsuccinate is a substituted alkyl group having from C1 to C8, such as methyl, ethyl or propyl.
In a further preferred embodiment, the starting dialkyl succinyl succinate is dimethyl succinyl succinate.
Preferably, the organic solvent is C1-C4 aliphatic alcohol, tetrahydrofuran, methyltetrahydrofuran, acetone, butanone, 1, 4-dioxane, acetonitrile, N-dimethylformamide, N-dimethylacetamide, dimethyl sulfoxide, or other water-miscible organic solvents.
Preferably, the basic 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.
Preferably, the mixed gas containing oxygen is oxygen and at least one of nitrogen, argon, carbon dioxide or air, wherein the volume concentration of oxygen is 5-100%.
In a further preferred embodiment, the oxygen-containing gas used is pure oxygen.
Preferably, the reducing agent aqueous solution is at least one selected from sodium sulfite solution, sodium bisulfite solution, sodium thiosulfate solution, sodium dithionite solution, hydrazine hydrate, hydroxylamine solution, hypophosphorous acid solution and phosphorous acid solution, and the mass fraction of the reducing agent in the reducing agent aqueous solution is preferably 10 wt% to 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 application are not limited to the precise range or value and should be understood to encompass values close to these ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual values, and between the individual values may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein. The technical solutions in the following embodiments can be combined with each other in principle to obtain a new technical solution, which should also be considered as specifically disclosed in the present invention.
The invention has the advantages and beneficial effects that:
the method for preparing the 2, 5-dihydroxy terephthalic acid by oxidizing the dialkyl succinyl succinate with the gas containing oxygen under the alkaline condition has the advantages of 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 diagram of the chemical reaction process of the method of the present invention;
FIG. 2 shows a NMR spectrum of 2, 5-dihydroxyterephthalic acid prepared in example 1 of the present invention.
Detailed Description
While the invention will be described in detail and with reference to the drawings and specific examples, it is to be understood that the following examples are included merely for purposes of illustration and are not intended to limit the scope of the invention, as other insubstantial modifications and adaptations of the invention may be made by those skilled in the art based on the teachings herein.
It is to be further understood that the various features described in the following detailed description may be combined in any suitable manner without departing from the scope of the invention. The invention is 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, as long as the technical solution formed by the combination does not depart from the idea of the present invention, and the technical solution formed by the combination is part of the original disclosure of the present specification, and also falls into the protection scope of the present invention.
The raw materials used in the examples are, if not particularly limited, those disclosed in the prior art, and may be, for example, obtained commercially directly or prepared according to the production methods disclosed in the prior art.
[ example 1 ]
The oxygen oxidation produces 2, 5-dihydroxyterephthalic acid, the reaction scheme is shown in figure 1.
11.4kg of dimethyl succinylsuccinate, 16kg of sodium hydroxide (the molar ratio of dimethyl succinylsuccinate to 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 percent hydrazine hydrate solution is added after the temperature is reduced, 1mol/L of sulfuric acid is added for neutralization until the pH value is 3.0, the mixture is cooled and filtered, 9.0kg of yellow powdery solid obtained after washing and drying a filter cake is 2, 5-dihydroxyterephthalic acid, and the yield is 91 percent.
5mg of 2, 5-dihydroxy terephthalic acid sample is dissolved in 0.5mL of dimethyl sulfoxide and uniformly dispersed by ultrasonic, and the attached figure 2 is obtained by testing with a Fourier nuclear magnetic resonance spectrometer.
[ example 2 ]
Preparing 2, 5-dihydroxyterephthalic acid by oxygen oxidation, adding 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), 3.84kg of water and 0.768kg of organic solvent into a reaction tank provided with a stirring, temperature-controlling and condensing device, introducing mixed gas of 90% oxygen and 10% argon, stirring and heating to 110 ℃, reacting for 60 hours, cooling, adding 0.026kg of 80% hydrazine hydrate solution, then adding 1mol/L hydrochloric acid to neutralize the mixed gas to have a pH value of 3.0, cooling and filtering, and washing and drying a filter cake to obtain 0.88kg of yellow powdery solid which is the 2, 5-dihydroxyterephthalic acid, wherein the yield is 89%.
[ example 3 ]
The preparation method comprises the steps of oxidizing with oxygen to prepare 2, 5-dihydroxyterephthalic acid, adding 1.42kg of dipropyl succinylsuccinate, 1.2kg of sodium hydroxide (namely the molar ratio of dimethyl succinylsuccinate to sodium hydroxide is 1: 6), 5.68kg of water and 2.84kg of organic solvent into a reaction tank provided with a stirring, temperature controlling and condensing device, introducing mixed gas of 80% by volume of oxygen and 20% of nitrogen, stirring and heating to 100 ℃, reacting for 50 hours, cooling, adding 0.043kg of 80% hydrazine hydrate solution, adding 1mol/L of phosphoric acid to neutralize the mixture to a pH value of 3.0, cooling and filtering, and washing and drying a filter cake to obtain 0.87kg of yellow powdery solid, namely the 2, 5-dihydroxyterephthalic acid with a yield of 88%.
[ example 4 ]
The preparation method comprises the steps of oxidizing oxygen to prepare 2, 5-dihydroxyterephthalic acid, adding 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), 7.8kg of water and 6.24kg of organic solvent into a reaction tank provided with a stirring, temperature controlling and condensing device, introducing mixed gas of 60% by volume of oxygen and 40% of carbon dioxide, stirring and heating to 90 ℃, reacting for 40 hours, cooling, adding 0.078kg of 80% hydrazine hydrate solution, adding 1mol/L of sulfuric acid to neutralize the mixed gas until the pH is 3.0, cooling and filtering, and washing and drying a filter cake to obtain 0.85kg of yellow powdery solid, namely the 2, 5-dihydroxyterephthalic acid, wherein the yield is 86%.
[ example 5 ] A method for producing a polycarbonate
The preparation method comprises the steps of oxidizing oxygen to prepare 2, 5-dihydroxyterephthalic acid, adding 1.70kg of diamyl succinyl succinate, 0.8kg of sodium hydroxide (namely the molar ratio of dimethyl succinyl succinate to sodium hydroxide is 1: 4), 10.2kg of water and 10.2kg of organic solvent into a reaction tank provided with a stirring, temperature controlling and condensing device, introducing mixed gas of 40% by volume of oxygen and 60% of argon, stirring and heating to 80 ℃, reacting for 30 hours, cooling, adding 0.102kg of 80% hydrazine hydrate solution, adding 1mol/L of sulfuric acid to neutralize the mixed gas until the pH is 3.0, cooling and filtering, washing and drying a filter cake to obtain 0.84kg of yellow powdery solid, namely the 2, 5-dihydroxyterephthalic acid, wherein the yield is 85%.
[ example 6 ]
The preparation method comprises the steps of oxidizing oxygen to prepare 2, 5-dihydroxyterephthalic acid, adding 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), 14.7kg of water and 17.7kg of organic solvent into a reaction tank provided with a stirring, temperature controlling and condensing device, introducing mixed gas of 20% by volume of oxygen and 80% of carbon dioxide, stirring and heating to 70 ℃, reacting for 20 hours, cooling, adding 0.147kg of 80% hydrazine hydrate solution, adding 1mol/L of hydrochloric acid to neutralize the pH to 3.0, cooling and filtering, and washing and drying a filter cake to obtain 0.82kg of yellow powdery solid, namely the 2, 5-dihydroxyterephthalic acid with the yield of 83%.
[ example 7 ]
The preparation method comprises the steps of oxidizing oxygen to prepare 2, 5-dihydroxyterephthalic acid, adding 1.98kg of diheptyl succinyl succinate, 0.56kg of potassium hydroxide (namely the molar ratio of dimethyl succinyl succinate to sodium hydroxide is 1: 2), 17.8kg of water and 26.7kg of organic solvent into a reaction tank provided with a stirring, temperature controlling and condensing device, introducing mixed gas of 10% by volume of oxygen and 90% of carbon dioxide, stirring and heating to 60 ℃, reacting for 10 hours, cooling, adding 0.178kg of 80% hydrazine hydrate solution, adding 1mol/L of hydrochloric acid to neutralize the mixture to a pH value of 3.0, cooling and filtering, and washing and drying a filter cake to obtain 0.81kg of yellow powdery solid, namely the 2, 5-dihydroxyterephthalic acid, wherein the yield is 82%.
[ example 8 ]
2, 5-dihydroxyterephthalic acid is prepared by oxidizing oxygen, 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), 21.2kg of water and 42.4kg of organic solvent are added into a reaction tank provided with a stirring, temperature control and condensing device, mixed gas of 5 percent by volume of oxygen and 95 percent of air is introduced, the mixture is stirred and heated to 40 ℃ for reaction for 2 hours, 80 percent hydrazine hydrate solution is added after the mixture is cooled and 0.212kg of 1mol/L hydrochloric acid is added for neutralization with the pH value of 3.0, the mixture is cooled and filtered, and 0.79kg of yellow powdery solid obtained after washing and drying of a filter cake is 2, 5-dihydroxyterephthalic acid, and the yield is 80 percent.
The invention has been described in detail with reference to specific embodiments and illustrative examples, but the description is not intended to be construed in a limiting sense. Those skilled in the art will appreciate 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, which fall within the scope of the present invention. The scope of the invention is defined by the appended claims.
Claims (9)
1. A method for preparing 2, 5-dihydroxyterephthalic acid by oxygen oxidation, comprising:
(1) using water or mixed solution of water and an organic solvent as a solvent medium, and oxidizing the succinyl succinic acid dialkyl ester by using oxygen-containing gas in the presence of an alkaline substance;
(2) adding a reducing agent aqueous solution after the reaction is finished;
(3) adding an acidic substance to acidify to obtain the 2, 5-dihydroxy terephthalic acid.
2. The method of claim 1, wherein the alkyl group in the starting dialkyl succinylsuccinate is a substituted alkyl group having from about C1 to about C8.
3. The method of claim 1, wherein the starting dialkyl succinyl succinate is dimethyl succinyl succinate.
4. The method of claim 1, wherein the organic solvent is C1-C4 aliphatic alcohol, tetrahydrofuran, methyltetrahydrofuran, acetone, butanone, 1, 4-dioxane, acetonitrile, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, or other water-miscible organic solvent.
5. The method of claim 1, wherein the basic 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.
6. The method of claim 1, wherein the oxygen-containing mixed gas is oxygen and at least one of nitrogen, argon, carbon dioxide or air, wherein the volume concentration of oxygen is 5% to 100%.
7. The method according to claim 1, wherein the aqueous solution of the reducing agent is selected from at least one of a sodium sulfite solution, a sodium bisulfite solution, a sodium thiosulfate solution, a sodium dithionite solution, hydrazine hydrate, a hydroxylamine solution, a hypophosphorous acid solution or a phosphorous acid solution, and preferably, the mass fraction of the reducing agent in the aqueous solution of the reducing agent is 10 wt% to 80 wt%.
8. The method of claim 1, wherein the acidic substance is sulfuric acid, hydrochloric acid, or phosphoric acid.
9. The method according to any one of claims 1 to 8, wherein the method is prepared by the following specific steps: adding dialkyl succinyl succinate, an alkaline substance and a solvent into a reaction tank provided with a stirring, temperature control and condensing device, introducing gas containing oxygen, stirring and heating, cooling, adding a reducing agent aqueous solution, adding an acidic substance into a reactor to neutralize the pH value to be 2-4, cooling and filtering, washing and drying a filter cake to obtain a target product, wherein the reaction yield is more than 80%; wherein the aqueous reducing agent solution is used to remove small amounts of over-oxidation products;
preferably, the molar ratio of the dialkyl succinylsuccinate to the alkaline substance is 1: (2-8), wherein the mass ratio of the dialkyl succinyl succinate to the water is 1: (2-10), wherein the mass ratio of water to the organic solvent is 1: (0-2), the reaction temperature is 40-130 ℃, the reaction time is 2-72 hours according to the amount of the added raw materials, and the mass ratio of the dialkyl succinyl succinate to the aqueous solution of the reducing agent is 1: (0.01 to 0.1);
the reaction route is as follows:
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115433084A (en) * | 2022-09-14 | 2022-12-06 | 天津科技大学 | Method for preparing 2, 5-dihydroxy terephthalic acid dialkyl ester by continuous flow oxidation |
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| 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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| 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 |
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| CN115433084A (en) * | 2022-09-14 | 2022-12-06 | 天津科技大学 | Method for preparing 2, 5-dihydroxy terephthalic acid dialkyl ester by continuous flow oxidation |
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