Method for synthesizing electronic grade 2,3,4-trihydroxybenzophenone

Abstract

The application belongs to the technical field of organic synthesis and particularly relates to a synthesis method of electronic-grade 2,3,4-trihydroxybenzophenone. The application comprises the following steps: catalytic reaction: taking water as a solvent, mixing water and a catalyst uniformly, adding pyrogallic acid, heating the system to 40-50 DEG C, continuously adding trichloromethylbenzene, performing insulation reaction, cooling the system to 10-15 DEG C after the reaction is completed, crystallizing and precipitating, and then filtering to obtain a crude wet product; purification treatment: removing impurities from the crude wet product to obtain the high-purity 2,3,4-trihydroxybenzophenone. The application does not need to react in an organic solvent system, is green and environmentally friendly, does not need nitrogen protection, has low production cost, and is suitable for industrialized processing and production, and the prepared 2,3,4-trihydroxybenzophenone has high purity and high yield.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of organic synthesis, and particularly relates to a synthesis method of electronic-grade 2,3,4-trihydroxybenzophenone. BACKGROUND

[0002] 2,3,4-trihydroxybenzophenone (3HBP for short) is a multifunctional aromatic ketone compound. Because the molecule simultaneously has phenolic hydroxyl and benzophenone structures, 2,3,4-trihydroxybenzophenone exhibits excellent ultraviolet light absorption performance, metal chelating ability and reactivity, and has become an important organic intermediate in the field of fine chemicals. As a photosensitive component in semiconductor photoresist, 2,3,4-trihydroxybenzophenone can effectively adjust the solubility of the exposed area; as an ultraviolet stabilizer in polymer materials, 2,3,4-trihydroxybenzophenone can delay material aging; in addition, 2,3,4-trihydroxybenzophenone also has wide application in medicine synthesis, dyes and functional additives.

[0003] In the prior art, extensive research has been carried out on the synthesis of 2,3,4-trihydroxybenzophenone. For example, in Japanese Patent Publication No. JPH06172252A, pyrogallol and benzoic acid are used as raw materials, tin chloride is used as a catalyst, and 2,3,4-trihydroxybenzophenone is synthesized under the action of phosphorus oxychloride. In German Patent DE50415, benzoyl chloride and pyrogallol are used to synthesize 2,3,4-trihydroxybenzophenone in the presence of zinc chloride. In Chinese Patent Publication No. CN111217685A, pyrogallol and benzoic acid are used as raw materials, and macroporous strong acid styrene cation exchange resin is used as a catalyst for preparation. In Chinese Patent Publication No. CN1313272A, pyrogallol is used as a starting material, and under the protection of inert gas, it is reacted with chlorobenzene in a binary mixed solvent under the catalysis of Lewis acid. After treatment with aromatic hydrocarbon solvent, 2,3,4-trihydroxybenzophenone is obtained.

[0004] However, these prior arts have the following defects: first, the use of organic solvents causes serious environmental and safety problems. Solvents such as methanol and toluene have strong toxicity, high volatility and flammability, which pose a threat to the health of production operators. At the same time, after the reaction is completed, a large amount of wastewater and waste gas containing organic solvents are generated, which is difficult and costly to treat, and the residual solvent is difficult to completely remove, which can easily cause environmental pollution and product solvent residue exceeding the standard. Second, the existing process has many reaction by-products, and the reaction yield is generally low. In addition, the polarity and solubility of the solvent have a significant impact on the reaction equilibrium and product precipitation behavior, often leading to incomplete product precipitation or wrapping impurities, reducing the effective yield. Moreover, the product obtained by the prior art has insufficient purity, especially high content of metal ion impurities, which cannot meet the demand of high-end semiconductor applications. Furthermore, the existing purification process is complex and costly. In order to obtain a product with high purity, multiple recrystallizations, column chromatography or high-temperature vacuum sublimation are often required. These processes are not only tedious and time-consuming, but also consume a large amount of solvent and result in a large amount of product loss, which is not conducive to large-scale production.

[0005] In summary, it is of great significance to develop a green and environmentally friendly, simple operation, high product yield and purity meeting the requirements of semiconductor grade synthesis method, which is also an urgent need for the development of the technical field. SUMMARY

[0006] The technical problem solved by the present application is to provide a green and environmentally friendly, simple operation, high product purity and suitable for industrial production synthesis method of 2,3,4-trihydroxybenzophenone.

[0007] The technical problem solved by the present application is solved by the following technical solution:

[0008] A synthesis method of electronic grade 2,3,4-trihydroxybenzophenone, comprising the following steps:

[0009] Catalytic reaction: using water as the solvent, mixing water and catalyst uniformly, adding pyrogallol, heating the system to 40-50℃, continuously adding trichlorobenzene, and carrying out incubation reaction. After the reaction is completed, the temperature is lowered to 10-15℃, and then crystallization is carried out. The crude product is obtained by filtration.

[0010] Purification treatment: removing impurities from the crude product to obtain high-purity 2,3,4-trihydroxybenzophenone.

[0011] Further, in the catalytic reaction, the catalyst comprises N,N-dimethylformamide or N-methylpyrrolidone.

[0012] Further, in the catalytic reaction, the mass-volume ratio of the pyrogallic acid and the solvent is 2-3 g:10 ml; the volume ratio of the trichloromethyl benzene and the solvent is 5-7:20; and the volume ratio of the catalyst and the solvent is 2-8:100.

[0013] Further, in the catalytic reaction, the trichloromethyl benzene is added in a dropwise manner under stirring, and the reaction is kept for 0.5-1.5 h after the dropwise addition is completed.

[0014] Further, in the catalytic reaction, the filter residue obtained after the crystallization and filtration is cleaned to obtain a crude wet product.

[0015] Further, in the purification process, the impurity removal includes a first impurity removal by mixing the wet crude product with a decolorizing solvent, activated carbon and a metal ion impurity removal agent; and a second impurity removal by mixing the dry crude product obtained after the first impurity removal with an ethanol solution and a metal ion impurity removal agent.

[0016] Further, in the first impurity removal, the mass-volume ratio of the wet crude product and the decolorizing solvent is 2-3 g:12 ml; the mass ratio of the wet crude product, the activated carbon and the metal ion impurity removal agent is 100-150:4-8:2-6; the impurity removal temperature is 55-75 ℃, and the impurity removal time is 1-3 h.

[0017] Preferably, the decolorizing solvent is methyl tert-butyl ether, or methyl tert-amyl ether, or ethylene glycol dimethyl ether, or a mixed solvent of n-heptane and ethyl acetate, or a mixed solvent of n-heptane and dimethyl carbonate, or a mixed solvent of hexane and ethyl acetate, or a mixed solvent of hexane and dimethyl carbonate, or a mixed solvent of petroleum ether and ethyl acetate, or a mixed solvent of petroleum ether and dimethyl carbonate.

[0018] Further, in the second impurity removal, the concentration of the ethanol solution is 30-50%, the volume-mass ratio of the ethanol solution and the wet crude product is 10-20 ml:2 g, the mass ratio of the metal ion impurity removal agent and the wet crude product is 2-6:100-150, the impurity removal temperature is 6-10 ℃, and the impurity removal time is 6-16 h.

[0019] Further, the metal ion impurity removal agent used in the first and second impurity removals includes oxalic acid, tartaric acid, cation resin, citric acid or ethylenediaminetetraacetic acid.

[0020] A 2,3,4-trihydroxybenzophenone prepared by the method described above, the yield of the 2,3,4-trihydroxybenzophenone is not less than 92%, and the purity of the 2,3,4-trihydroxybenzophenone is not less than 99%.

[0021] Beneficial effects: The electronic-grade 2,3,4-trihydroxybenzophenone synthesis method of the present invention uses water as the reaction solvent for the catalytic reaction, eliminating the need for reaction in an organic solvent system. It is green, environmentally friendly, simple, readily available, and has high production safety. The purified product has high purity, high yield, and low metal ion impurity content, which can better meet the requirements for use in semiconductor materials.

[0022] The present invention discloses an electronic-grade method for synthesizing 2,3,4-trihydroxybenzophenone, which does not require nitrogen protection during the reaction, has a low reaction temperature, uses an aqueous solvent, and allows the product to precipitate in water immediately after the reaction. The method minimizes the oxidation of raw materials during preparation and employs a two-stage purification process, resulting in a product with a purity of no less than 99%, a yield of no less than 92%, and metal ion impurities below 50 ppb. Furthermore, the purification method is simple, and the solvent used in the purification process can be recycled, reducing losses and costs, and is beneficial for industrial production. Attached Figure Description

[0023] Figure 1 The 2,3,4-trihydroxybenzophenone product obtained in Example 1 1 H-NMR spectrum.

[0024] Figure 2 The image shows the HPLC chromatogram of the 2,3,4-trihydroxybenzophenone product obtained in Example 1.

[0025] Figure 3 The image shows the HPLC chromatogram of the 2,3,4-trihydroxybenzophenone product obtained in Example 2.

[0026] Figure 4 The image shows the HPLC chromatogram of the 2,3,4-trihydroxybenzophenone product obtained in Example 3.

[0027] Figure 5 The HPLC chromatogram of the 2,3,4-trihydroxybenzophenone product obtained from Comparative Example 1 is shown.

[0028] Figure 6 The HPLC chromatogram of the 2,3,4-trihydroxybenzophenone product obtained from Comparative Example 2 is shown.

[0029] Figure 7 The HPLC chromatogram of the 2,3,4-trihydroxybenzophenone product obtained from Comparative Example 3 is shown.

[0030] Figure 8 The image shows the HPLC chromatogram of the 2,3,4-trihydroxybenzophenone product obtained in Comparative Example 4.

[0031] Figure 9 The HPLC chromatogram of the 2,3,4-trihydroxybenzophenone product obtained in Comparative Example 5 is shown. DETAILED DESCRIPTION

[0032] In order to make the technical means, creative features, purposes and effects of the present application easy to understand, the present application is further described below in combination with specific examples. Example 1

[0033] The synthesis method of the electronic grade 2,3,4-trihydroxybenzophenone described in this embodiment comprises the following steps:

[0034] Catalytic reaction: 200 ml of water is used as a solvent, 4 ml of DMF (N, N-dimethylformamide) is added into the water and mixed uniformly, 50 g of pyrogallic acid is added, the system is warmed to 45°C, the system is kept in a stirring state, then chloroform is added into the system in a dropwise manner, the dropwise amount of chloroform is 60 ml, after the dropwise addition is completed, the reaction is carried out for 1 h, the temperature is lowered to 12°C, crystallization is carried out, then filtration is carried out, the obtained filter residue is washed with 50°C warm water, and after being dried, 130 g of wet crude product is obtained.

[0035] Purification treatment: the wet crude product is sequentially subjected to primary impurity removal and secondary impurity removal, wherein the primary impurity removal is: 130 g of wet crude product is added into 600 ml of n-heptane, then 6 g of activated carbon and 4 g of oxalic acid are added, the temperature is raised to 70°C, the color is removed for 1.5 h, then filtration is carried out, the obtained filtrate is concentrated to dryness to obtain dry crude product; the secondary impurity removal is: the dry crude product is mixed with 600 ml of 40% concentration ethanol, dissolved at 70°C, then 4 g of oxalic acid is added, mixed uniformly, then placed at 8°C for 12 h, then filtration is carried out to obtain wet fine product; the wet fine product is dried to obtain 86 g of yellow powder, which is the 2,3,4-trihydroxybenzophenone product.

[0036] The nuclear magnetic spectrum of the 2,3,4-trihydroxybenzophenone product obtained in this embodiment is as shown in Figure 1 . 1 H NMR (400 MHz, Chloroform- d ) 12.70 (s, 1H), 7.70-7.63 (m, 2H), 7.62-7.54 (m, 1H). 7.54-7.43 (m, 2H), 7.15 (d, J = 8.9 Hz. 1H), 6.51 (d, J = 8.9 Hz. 1H). 6.21 (d, J = 3.5 Hz. 1H), 5.87 (d, J = 3.5 Hz. 1H).

[0037] The HPLC chart of the 2,3,4-trihydroxybenzophenone product obtained in this embodiment is as shown in Figure 2 . Example 2

[0038] The electronic grade 2,3,4-trihydroxybenzophenone synthesis method described in this embodiment comprises the following steps:

[0039] Catalytic reaction: 200 ml of water was used as the solvent, 6 mL of N-methyl pyrrolidone was added to the water and mixed evenly, 50 g of pyrogallic acid was added, the system was heated to 50°C, the system was kept stirring, then trichloromethylbenzene was added to the system in a dropwise manner, the dropwise amount of trichloromethylbenzene was 70 ml, after the dropwise addition was completed, the reaction was carried out for 1 h, the temperature was lowered to 15°C, crystallization was carried out, then filtration was carried out, the obtained filter residue was washed with 50°C warm water, and after being dried, 128 g of wet crude product was obtained.

[0040] Purification treatment: the wet crude product was sequentially subjected to primary impurity removal and secondary impurity removal, wherein the primary impurity removal was: 128 g of wet crude product was added to 600 ml of n-heptane, then 7 g of activated carbon and 4 g of citric acid were added, heating was carried out to 55°C, decolorization and impurity removal was carried out for 1.5 h, then filtration was carried out, the obtained filtrate was concentrated to dryness to obtain dry crude product; the secondary impurity removal was: the dry crude product was mixed with 600 ml of 40% concentration ethanol, dissolved at 70°C, then 4 g of citric acid was added, after being mixed evenly, it was placed at 8°C for 12 h, then filtration was carried out to obtain wet fine product; the wet fine product was dried to obtain 84 g of yellow powder, which was the 2,3,4-trihydroxybenzophenone product.

[0041] The HPLC chart of the 2,3,4-trihydroxybenzophenone product obtained in this embodiment is shown in Figure 3 . Example 3

[0042] The electronic grade 2,3,4-trihydroxybenzophenone synthesis method described in this embodiment comprises the following steps:

[0043] Catalytic reaction: 200 ml of water was used as the solvent, 6 mL of N-methyl pyrrolidone was added to the water and mixed evenly, 50 g of pyrogallic acid was added, the system was heated to 50°C, the system was kept stirring, then trichloromethylbenzene was added to the system in a dropwise manner, the dropwise amount of trichloromethylbenzene was 70 ml, after the dropwise addition was completed, the reaction was carried out for 1 h, the temperature was lowered to 15°C, crystallization was carried out, then filtration was carried out, the obtained filter residue was washed with 50°C warm water, and after being dried, 128 g of wet crude product was obtained.

[0044] Purification treatment: the crude wet product was subjected to once impurity removal and twice impurity removal in turn, wherein the once impurity removal was: 132 g of the crude wet product was added into 700 ml of n-heptane, then 6 g of activated carbon and 8 g of tartaric acid were added, and the mixture was heated to 65°C for 1.5 h for decolorization and impurity removal, then the mixture was filtered, and the obtained filtrate was concentrated to dryness to obtain dry crude product; the twice impurity removal was: the dry crude product was mixed with 600 ml of 40% ethanol, and the mixture was dissolved at 70°C, then 4 g of tartaric acid was added, and the mixture was uniformly mixed and then statically placed at 10°C for 12 h, then the mixture was filtered to obtain wet fine product; the wet fine product was dried to obtain 85 g of yellow powder, which was 2,3,4-trihydroxybenzophenone product.

[0045] The HPLC chart of the 2,3,4-trihydroxybenzophenone product obtained in the example is shown in Figure 4 .

[0046] Comparative Example 1

[0047] In the comparative example, nitrogen protection was adopted during the catalytic reaction; in the purification treatment step, the crude wet product was subjected to twice impurity removal treatment without decolorization and impurity removal, and the rest was the same as in Example 1, and 84 g of yellow powder was obtained. The HPLC chart of the product obtained in the comparative example is shown in Figure 5 .

[0048] Comparative Example 2

[0049] In the comparative example, no catalyst DMF was added during the catalytic reaction, and the rest was the same as in Example 1, and 75 g of yellow powder was obtained. The HPLC chart of the product obtained in the comparative example is shown in Figure 6 .

[0050] Comparative Example 3

[0051] In the comparative example, no metal ion impurity remover was added during the purification treatment, and the twice impurity removal was: the dry crude product was mixed with 200 ml of 40% ethanol, and the rest was the same as in Example 3. 83 g of yellow powder was obtained. The HPLC chart of the product obtained in the comparative example is shown in Figure 7 .

[0052] Comparative Example 4

[0053] In the comparative example, the reaction temperature during the catalytic reaction was 60°C, and the rest was the same as in Example 1, and 70 g of brownish yellow powder was obtained. The HPLC chart of the product obtained in the comparative example is shown in Figure 8 .

[0054] Comparative Example 5

[0055] In the comparative example, the concentration of ethanol during the purification treatment was 60%, and the rest was the same as in Example 3. 85 g of yellow powder was obtained. The HPLC chart of the product obtained in the comparative example is shown in Figure 9 .

[0056] The liquid chromatogram of the 2,3,4-trihydroxybenzophenone product prepared in Examples 1-3 and Comparative Examples 1-5 is shown in Figure 1. Figures 2-9

[0057] The yield and purity of the 2,3,4-trihydroxybenzophenone product prepared in Examples 1-3 and Comparative Examples 1-5 are shown in Table 1. The 26 metal ion impurities were detected by ICP-MS, and the results are shown in Table 2.

[0058]

[0059] Table 2: Detection of metal impurities in the 2,3,4-trihydroxybenzophenone product in each example and comparative example

[0060] (unit: ppb)

[0061]

[0062] From the above description and Table 1 and Table 2, it can be seen that the 2,3,4-trihydroxybenzophenone prepared by the present application has high purity, high yield, and low metal ion impurity content, which is much better than the prior art and has good value for large-scale production and promotion. In the present application, the selection of catalyst type, the setting of raw material ratio, the control of catalytic reaction conditions, and the purification treatment are all critical, and improper control will result in unsatisfactory results. In addition, as shown in Comparative Example 1, the reaction results under nitrogen protection are not significantly different, and the present application does not need to be carried out under nitrogen protection, which is more simple in actual operation and lower in production cost.

[0063] The above shows and describes the basic principles, main features, and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.​

Claims

1. A process for the synthesis of electronic grade 2,3,4-trihydroxybenzophenone, characterized by, The method comprises the following steps: The catalytic reaction is carried out as follows: the water and the catalyst are mixed uniformly, pyrogallic acid is added, the system is heated to 40-50 DEG C, chloroform is continuously added, and the reaction is carried out after being kept warm; after the reaction is completed, the temperature is lowered to 10-15 DEG C, crystallization is carried out, and then the crude wet product is obtained by filtration; the catalyst comprises N, N-dimethylformamide or N-methylpyrrolidone; The purification treatment is carried out as follows: the crude wet product is impurity-removed, the impurity-removal comprises one-time impurity-removal of the crude wet product mixed with a decolorizing solvent, activated carbon and a metal ion impurity-removal agent; and two-time impurity-removal of the dry crude product obtained by filtration and concentration after the one-time impurity-removal is mixed with an ethanol solution and a metal ion impurity-removal agent; 2, 3, 4-trihydroxybenzophenone is obtained.

2. The process for synthesis of electronic grade 2,3,4-trihydroxybenzophenone as claimed in claim 1, wherein, In the catalytic reaction, the mass-volume ratio of the pyrogallic acid to the solvent is 2-3 g:10 ml; the volume ratio of the chloroform to the solvent is 5-7:20; and the volume ratio of the catalyst to the solvent is 2-8:

100.

3. The process for synthesis of electronic grade 2,3,4-trihydroxybenzophenone as claimed in claim 1, wherein, In the catalytic reaction, the chloroform is added in a dropwise manner under the condition of stirring, and the reaction is kept warm for 0.5-1.5 h after the dropwise addition is completed.

4. The process for synthesis of electronic grade 2,3,4-trihydroxybenzophenone as claimed in claim 1, wherein, After the crystallization is carried out, the filter residue obtained by filtration is washed to obtain the crude wet product.

5. The process for synthesis of electronic grade 2,3,4-trihydroxybenzophenone as claimed in claim 1, wherein, In the one-time impurity-removal, the mass-volume ratio of the crude wet product to the decolorizing solvent is 2-3 g:12 ml; the mass ratio of the crude wet product to the activated carbon and the metal ion impurity-removal agent is 100-150:4-8:2-6; the impurity-removal temperature is 55-75 DEG C, and the impurity-removal time is 1-3 h.

6. The process for synthesis of electronic grade 2,3,4-trihydroxybenzophenone as claimed in claim 1, wherein, In the two-time impurity-removal, the concentration of the ethanol solution is 30-50%, the volume-mass ratio of the ethanol solution to the crude wet product is 10-20 ml:2 g; the mass ratio of the metal ion impurity-removal agent to the crude wet product is 2-6:100-150; the impurity-removal temperature is 6-10 DEG C, and the impurity-removal time is 6-16 h.

7. The process for synthesis of electronic grade 2,3,4-trihydroxybenzophenone as claimed in claim 1, wherein, The metal ion impurity-removal agents used in the one-time impurity-removal and the two-time impurity-removal comprise oxalic acid, tartaric acid, cation resin, citric acid, ethylenediaminetetraacetic acid or ethylenediaminetetraacetic acid disodium salt.

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