CN117164442A - Preparation method of 4-chloro-4' -hydroxybenzophenone - Google Patents
Preparation method of 4-chloro-4' -hydroxybenzophenone Download PDFInfo
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- CN117164442A CN117164442A CN202311118628.7A CN202311118628A CN117164442A CN 117164442 A CN117164442 A CN 117164442A CN 202311118628 A CN202311118628 A CN 202311118628A CN 117164442 A CN117164442 A CN 117164442A
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- Prior art keywords
- chloro
- chlorobenzene
- aluminum trichloride
- hydroxybenzophenone
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- RUETVLNXAGWCDS-UHFFFAOYSA-N (4-chlorophenyl)-(4-hydroxyphenyl)methanone Chemical compound C1=CC(O)=CC=C1C(=O)C1=CC=C(Cl)C=C1 RUETVLNXAGWCDS-UHFFFAOYSA-N 0.000 title claims abstract description 15
- 238000002360 preparation method Methods 0.000 title claims abstract description 9
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 claims abstract description 50
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 claims abstract description 36
- RDOXTESZEPMUJZ-UHFFFAOYSA-N anisole Chemical compound COC1=CC=CC=C1 RDOXTESZEPMUJZ-UHFFFAOYSA-N 0.000 claims abstract description 28
- 238000000034 method Methods 0.000 claims abstract description 20
- RKIDDEGICSMIJA-UHFFFAOYSA-N 4-chlorobenzoyl chloride Chemical compound ClC(=O)C1=CC=C(Cl)C=C1 RKIDDEGICSMIJA-UHFFFAOYSA-N 0.000 claims abstract description 17
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 17
- 238000006243 chemical reaction Methods 0.000 claims abstract description 16
- 238000001914 filtration Methods 0.000 claims abstract description 15
- UZKWTJUDCOPSNM-UHFFFAOYSA-N methoxybenzene Substances CCCCOC=C UZKWTJUDCOPSNM-UHFFFAOYSA-N 0.000 claims abstract description 14
- JJVJYPSXZCEIEQ-UHFFFAOYSA-N (4-chlorophenyl)-(4-methoxyphenyl)methanone Chemical compound C1=CC(OC)=CC=C1C(=O)C1=CC=C(Cl)C=C1 JJVJYPSXZCEIEQ-UHFFFAOYSA-N 0.000 claims abstract description 11
- 238000010992 reflux Methods 0.000 claims abstract description 9
- 230000017858 demethylation Effects 0.000 claims abstract description 8
- 238000010520 demethylation reaction Methods 0.000 claims abstract description 8
- 239000007787 solid Substances 0.000 claims abstract description 8
- 239000002904 solvent Substances 0.000 claims abstract description 7
- 238000006555 catalytic reaction Methods 0.000 claims abstract description 4
- 239000012467 final product Substances 0.000 claims abstract description 4
- 230000003301 hydrolyzing effect Effects 0.000 claims abstract 2
- 230000015572 biosynthetic process Effects 0.000 claims description 4
- 238000003786 synthesis reaction Methods 0.000 claims description 4
- 239000005995 Aluminium silicate Substances 0.000 claims description 3
- 235000012211 aluminium silicate Nutrition 0.000 claims description 3
- 239000003795 chemical substances by application Substances 0.000 claims description 3
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 claims description 3
- 239000000047 product Substances 0.000 abstract description 24
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 abstract description 18
- 230000007062 hydrolysis Effects 0.000 abstract description 16
- 238000006460 hydrolysis reaction Methods 0.000 abstract description 16
- 239000012535 impurity Substances 0.000 abstract description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 14
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 abstract description 6
- 229910052782 aluminium Inorganic materials 0.000 abstract description 6
- 238000004519 manufacturing process Methods 0.000 abstract description 6
- 230000007613 environmental effect Effects 0.000 abstract description 5
- 238000009776 industrial production Methods 0.000 abstract description 5
- 239000002351 wastewater Substances 0.000 abstract description 4
- 239000003960 organic solvent Substances 0.000 abstract description 3
- 238000009835 boiling Methods 0.000 abstract description 2
- 238000005119 centrifugation Methods 0.000 description 11
- 239000012043 crude product Substances 0.000 description 11
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 239000000463 material Substances 0.000 description 6
- 239000000203 mixture Substances 0.000 description 6
- SCYULBFZEHDVBN-UHFFFAOYSA-N 1,1-Dichloroethane Chemical compound CC(Cl)Cl SCYULBFZEHDVBN-UHFFFAOYSA-N 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000012452 mother liquor Substances 0.000 description 3
- 239000010413 mother solution Substances 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000004042 decolorization Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 239000003814 drug Substances 0.000 description 2
- YMTINGFKWWXKFG-UHFFFAOYSA-N fenofibrate Chemical compound C1=CC(OC(C)(C)C(=O)OC(C)C)=CC=C1C(=O)C1=CC=C(Cl)C=C1 YMTINGFKWWXKFG-UHFFFAOYSA-N 0.000 description 2
- 229960002297 fenofibrate Drugs 0.000 description 2
- 239000000543 intermediate Substances 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000005727 Friedel-Crafts reaction Methods 0.000 description 1
- 239000005909 Kieselgur Substances 0.000 description 1
- 238000005904 alkaline hydrolysis reaction Methods 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical class [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000055 hyoplipidemic effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/584—Recycling of catalysts
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a preparation method of 4-chloro-4 '-hydroxybenzophenone, which comprises the steps of generating 4-chloro-4' -methoxybenzophenone at low temperature under the catalysis of anhydrous aluminum trichloride from anisole, p-chlorobenzoyl chloride and chlorobenzene, centrifuging out solid, adding a small amount of aluminum trichloride into the solid in chlorobenzene solvent, carrying out reflux reaction for 2 hours for demethylation, adding diatomite for filtering and decoloring, and hydrolyzing at low temperature to obtain a final product which is white. According to the preparation method of the 4-chloro-4' -hydroxybenzophenone, the use of an organic solvent toluene is eliminated, chlorobenzene is changed, the boiling point of the chlorobenzene is higher, the reaction is more thorough in the demethylation process, diatomite is added in the later stage to adsorb aluminum mud impurities, the color of the obtained product is white, the purity can reach more than 99.5%, the maximum single impurity is not more than 0.1%, the production peculiar smell is small, the cost is reduced, a small amount of water is added in the hydrolysis process to disperse, the waste water amount is reduced, and the environmental protection performance is good; the method has mild reaction conditions and simple post-treatment, and is suitable for industrial production.
Description
Technical Field
The invention relates to the technical field of synthesis of human medicine bulk drug intermediates, in particular to a preparation method of 4-chloro-4' -hydroxybenzophenone.
Background
4-chloro-4' -hydroxybenzophenone has very wide application and large market demand. The fenofibrate is mainly used as an important intermediate of the hypolipidemic fenofibrate, the color of the product can be brought into the next reaction, the color of the final product can meet the market demand by additionally adding a decoloring step, and the decoloring effect is not obvious. How to find a production process with mild reaction and reduced cost is an important index of whether the product can continuously develop.
The traditional process generally uses dichloroethane as a solvent, anisole and p-chlorobenzoyl chloride are catalyzed by aluminum trichloride to synthesize 4-chloro-4 '-methoxybenzophenone, the dichloroethane is concentrated and distilled, aluminum trichloride and toluene are added for demethylation, 4-chloro-4' -hydroxybenzophenone crude product is obtained by hydrolysis, 5% sodium hydroxide solution is added into the crude product to adjust the pH to 11, the aluminum salt wrapped by the materials is removed by filtration, the pH is adjusted to 1, and the final product is obtained by centrifugation. The product obtained by the method has a crude product color of redness and orange color after being treated by low-concentration alkaline water. Two organic solvents are introduced in the whole reaction process, wherein toluene is an easily-toxic solvent, and particularly, the material is easily damaged at high temperature in the later period of concentrating dichloroethane. In the post refining process, the sodium salt of the product has poor water solubility, a large amount of waste water is generated, and the product is very difficult to filter because a large amount of aluminum mud exists in the filtering and color removing process, the purity of the product is basically maintained to be about 99 percent, and the maximum single impurity is more than 0.3 percent.
Also, enterprises use chlorobenzene as a solvent, all anhydrous aluminum trichloride is added at one time to react at normal temperature to generate 4-chloro-4' -methoxybenzophenone, then the temperature is directly raised for demethylation, and the product is obtained by hydrolysis, so that a large amount of water is required to be added for complete hydrolysis. The product is red in color, and because the product wraps a large amount of aluminum mud generated by aluminum trichloride, the reaction process is not thorough and needs to be refined by alkaline hydrolysis. In the refining process, a large amount of wastewater is generated and the filtering is difficult, the color is light yellow, the purity is 99%, and the maximum single impurity is more than 0.3%.
However, the existing preparation method still has some defects, the product has poor filtering effect, the water consumption for later hydrolysis is too large, the environmental protection is poor, and the industrial production is not easy.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a preparation method of 4-chloro-4' -hydroxybenzophenone, which aims to solve the problems of poor product filtering effect, too large water consumption for later hydrolysis, poor environmental protection, difficult industrial production and the like.
In order to achieve the aim of the invention, the invention adopts the following technical scheme: a process for preparing 4-chloro-4 '-hydroxy diphenyl ketone includes such steps as preparing 4-chloro-4' -methoxy diphenyl ketone from anisole, p-chlorobenzoyl chloride and chlorobenzene under the catalysis of anhydrous aluminium trichloride, centrifuging to obtain solid, adding small amount of aluminium trichloride to the solid in chlorobenzene solvent, reflux reaction for 2 hr for demethylation, adding diatomite, filtering for decolourization and low-temp hydrolysis.
Further, p-chlorobenzoyl chloride is dropwise added in the synthesis process of the 4-chloro-4' -methoxybenzophenone, and the temperature is controlled to be 0-10 ℃.
Further, the mole ratio of anisole, p-chlorobenzoyl chloride, anhydrous aluminum trichloride and demethylated anhydrous aluminum trichloride is 1:0.95-1.05:0.95-1:0.5-0.55.
Further, the two dosages of chlorobenzene are three times of the total weight of the twice aluminum trichloride.
Further, the diatomite accounts for 3% -5% of the total anhydrous aluminum trichloride.
Further, the decoloring agent may be diatomaceous earth or kaolin.
The beneficial effects of the invention are as follows:
according to the preparation method of the 4-chloro-4' -hydroxybenzophenone, one-step centrifugation is added, most aluminum mud generated by anhydrous aluminum trichloride is removed, and the method is a main cause for color of products; meanwhile, the impurity generated by the part is removed, which is also the key for improving the quality of the subsequent products; the diatomite has adsorption and filtration assisting effects, so that the production efficiency is improved; meanwhile, the use of toluene as an organic solvent is innovated, the toluene is changed into chlorobenzene, the boiling point of the chlorobenzene is higher, the reaction is more thorough in the demethylation process, diatomite is added in the later stage to adsorb aluminum mud impurities, the color of the product is white, the purity can reach more than 99.5%, the maximum single impurity is not more than 0.1%, the production peculiar smell is small, the cost is reduced, a small amount of water is added in the hydrolysis process to disperse, the waste water quantity is reduced, and the environmental protection performance is good; the method has mild reaction conditions, simple post-treatment and short flow, and is suitable for industrial production.
Detailed Description
The invention is further described below in connection with specific examples.
A process for preparing 4-chloro-4 '-hydroxy diphenyl ketone includes such steps as preparing 4-chloro-4' -methoxy diphenyl ketone from anisole, p-chlorobenzoyl chloride and chlorobenzene under the catalysis of anhydrous aluminium trichloride, centrifuging to obtain solid, adding small amount of aluminium trichloride to the solid in chlorobenzene solvent, reflux reaction for 2 hr for demethylation, adding diatomite, filtering for decolourization and low-temp hydrolysis.
P-chlorobenzoyl chloride is dropwise added in the synthesis process of the 4-chloro-4' -methoxybenzophenone, and the temperature is controlled to be 0-10 ℃.
The mole ratio of anisole, p-chlorobenzoyl chloride, anhydrous aluminum trichloride and demethylated anhydrous aluminum trichloride is 1:0.95-1.05:0.95-1:0.5-0.55.
The two dosages of chlorobenzene are three times of the total weight of the two aluminum trichloride.
The diatomite accounts for 3% -5% of the total amount of the anhydrous aluminum trichloride.
The decoloring agent can be diatomite or kaolin.
Comparative example one: 150 g of dichloroethane, 19 g of anisole, 22 g of anhydrous aluminum trichloride, 30 g of p-chlorobenzoyl chloride at 20 ℃ are added into a 500 ml three-port bottle, after the dripping is finished, the mixture is heated and refluxed for 1 hour, the dichloroethane is distilled until no liquid flows out, the pressure is reduced for half an hour, 100 g of toluene is added, 11 g of anhydrous aluminum trichloride is refluxed for 2 hours, the temperature is reduced for 20 ℃, 300 ml of water is added for hydrolysis and centrifugation, 33.5 g of reddish crude products are obtained, 250 ml of 5% sodium hydroxide solution is added to adjust the PH to 11 after the crude products are dried, insoluble impurities are removed by filtration, the mother solution is adjusted to PH to 1 by 15% hydrochloric acid, the orange yellow products are obtained by centrifugation, the purity is 99.2%, and the maximum single impurity is 0.4%.
Comparative example two: 100 g of chlorobenzene, 19 g of anisole, 33 g of anhydrous aluminum trichloride, 30 g of p-chlorobenzoyl chloride is dropwise added at 20 ℃ into a 500 ml three-port bottle, the dropwise addition is carried out for 2 hours, the temperature is slowly raised to reflux for two hours, 300 ml of water is cooled and added for hydrolysis and centrifugation, 33.3 g of red crude product is obtained, after drying, 250 ml of 5% sodium hydroxide solution is added for regulating the PH to 11, insoluble impurities are removed by filtration, the mother solution is regulated to PH to 1 by 15% hydrochloric acid, the light yellow product is obtained by centrifugation, the purity is 99.3%, and the maximum single impurity is 0.35%.
Embodiment one: 100 g of chlorobenzene, 19 g of anisole, 22 g of anhydrous aluminum trichloride, 30 g of p-chlorobenzoyl chloride is dropwise added at 5 ℃ into a 500 ml three-port bottle, after the dropwise addition is finished, the temperature is slowly raised to 20 ℃ and kept for 2 hours after the materials begin to separate out, the 4-chloro-4' methoxybenzophenone crude product is obtained by centrifugation, the crude product is put into a reaction bottle, 100 g of new chlorobenzene, 11 g of anhydrous aluminum trichloride are slowly raised to reflux for 2 hours, 1 g of diatomite is added after the whole solution is completely dissolved, the mixture is stirred for half an hour and then filtered, and 100 ml of water is added into the mother liquor for hydrolysis, so that 30.8 g of white product with the purity of 99.87% and the maximum single impurity of 0.03% is obtained.
Embodiment two: 100 g of chlorobenzene, 19 g of anisole, 22 g of anhydrous aluminum trichloride, 30 g of p-chlorobenzoyl chloride is dropwise added at 20 ℃ into a 500 ml three-port bottle, after the dropwise addition is finished, the temperature is slowly raised to 20 ℃ and kept for 2 hours after the materials begin to separate out, the 4-chloro-4' methoxybenzophenone crude product is obtained by centrifugation, 100 g of fresh chlorobenzene, 11 g of anhydrous aluminum trichloride are added into a reaction bottle, the temperature is slowly raised to reflux for 2 hours, 1 g of diatomite is added after the total dissolution, the mixture is stirred for half an hour and then filtered, and 100 ml of water is added into the mother liquor for hydrolysis, thus obtaining 30.5 g of light yellow product with the purity of 99.55% and the maximum single impurity of 0.12%.
Embodiment III: 100 g of chlorobenzene, 19 g of anisole, 22 g of anhydrous aluminum trichloride, 30 g of p-chlorobenzoyl chloride is dropwise added at 20 ℃ into a 500 ml three-port bottle, after the dropwise addition is completed, the temperature is slowly raised to 20 ℃ and kept for 2 hours after the materials begin to separate out, the 4-chloro-4' methoxybenzophenone crude product is obtained by centrifugation, 100 g of fresh chlorobenzene, 11 g of anhydrous aluminum trichloride are added into a reaction bottle, the temperature is slowly raised to reflux for 2 hours, the filtration speed is slowed after the mixture is stirred for half an hour after the mixture is completely dissolved, and the mother liquor is added with 100 ml of water for hydrolysis, thus obtaining 30.6 g of light yellow product with the purity of 99.42% and the maximum single impurity of 0.16%.
Embodiment four: 100 g of chlorobenzene, 19 g of anisole, 33 g of anhydrous aluminum trichloride, 30 g of p-chlorobenzoyl chloride is dropwise added at 5 ℃ into a 500 ml three-port bottle, after the dropwise addition is completed, the temperature is slowly raised to 20 ℃ and kept for 2 hours after the materials begin to separate out, the 4-chloro-4' methoxybenzophenone crude product is obtained by centrifugation, 100 g of fresh chlorobenzene is added into a reaction bottle, the temperature is slowly raised to reflux for 2 hours, 1 g of diatomite is added after the whole solution is completely dissolved, the mixture is stirred for half an hour and then filtered, the filtering speed is reduced, 100 ml of water is added into the mother solution for hydrolysis, and 31.5 g of light yellow product with the purity of 95.22% and the maximum single impurity of 3.45% is obtained. The raw materials do not react thoroughly.
In conclusion, it can be concluded that the anhydrous aluminum trichloride is added twice, the Friedel-crafts reaction is carried out at low temperature to be beneficial to the color and purity of the product, one-step centrifugation is added in the middle to remove the color brought by aluminum mud and a part of generated impurities, and diatomite is added subsequently, so that the product color can be adsorbed, the product filtering speed can be increased, the water consumption for later hydrolysis is greatly reduced, the environmental friendliness is good, and the industrial production is easy.
The above description is illustrative of the preferred embodiments of the present invention and is not intended to limit the scope of the present invention, but is to be accorded the full scope of the claims.
Claims (6)
1. A preparation method of 4-chloro-4 '-hydroxybenzophenone is characterized by comprising the steps of generating 4-chloro-4' -methoxybenzophenone at low temperature under the catalysis of anhydrous aluminum trichloride from anisole, p-chlorobenzoyl chloride and chlorobenzene, centrifuging out solid, adding a small amount of aluminum trichloride into the solid in chlorobenzene solvent, carrying out reflux reaction for 2 hours for demethylation, adding diatomite for filtering and decoloring, and hydrolyzing at low temperature to obtain a final product which is white.
2. The method for preparing 4-chloro-4' -hydroxybenzophenone according to claim 1, wherein: p-chlorobenzoyl chloride is dropwise added in the synthesis process of the 4-chloro-4' -methoxybenzophenone, and the temperature is controlled to be 0-10 ℃.
3. The method for preparing 4-chloro-4' -hydroxybenzophenone according to claim 1, wherein: the mole ratio of anisole, p-chlorobenzoyl chloride, anhydrous aluminum trichloride and demethylated anhydrous aluminum trichloride is 1:0.95-1.05:0.95-1:0.5-0.55.
4. The method for preparing 4-chloro-4' -hydroxybenzophenone according to claim 1, wherein: the two dosages of chlorobenzene are three times of the total weight of the two aluminum trichloride.
5. The method for preparing 4-chloro-4' -hydroxybenzophenone according to claim 1, wherein: the diatomite accounts for 3% -5% of the total amount of the anhydrous aluminum trichloride.
6. The method for preparing 4-chloro-4' -hydroxybenzophenone according to claim 1, wherein: the decoloring agent can be diatomite or kaolin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311118628.7A CN117164442A (en) | 2023-09-01 | 2023-09-01 | Preparation method of 4-chloro-4' -hydroxybenzophenone |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311118628.7A CN117164442A (en) | 2023-09-01 | 2023-09-01 | Preparation method of 4-chloro-4' -hydroxybenzophenone |
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| Publication Number | Publication Date |
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| CN117164442A true CN117164442A (en) | 2023-12-05 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202311118628.7A Pending CN117164442A (en) | 2023-09-01 | 2023-09-01 | Preparation method of 4-chloro-4' -hydroxybenzophenone |
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| CN (1) | CN117164442A (en) |
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2023
- 2023-09-01 CN CN202311118628.7A patent/CN117164442A/en active Pending
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