CN114671753A - Synthetic method of 3-chloro-4-hydroxybenzoic acid - Google Patents
Synthetic method of 3-chloro-4-hydroxybenzoic acid Download PDFInfo
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- CN114671753A CN114671753A CN202210198979.2A CN202210198979A CN114671753A CN 114671753 A CN114671753 A CN 114671753A CN 202210198979 A CN202210198979 A CN 202210198979A CN 114671753 A CN114671753 A CN 114671753A
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- Prior art keywords
- hydroxybenzoic acid
- chloro
- stirring
- putting
- synthesizing
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- QGNLHMKIGMZKJX-UHFFFAOYSA-N 3-chloro-4-hydroxybenzoic acid Chemical compound OC(=O)C1=CC=C(O)C(Cl)=C1 QGNLHMKIGMZKJX-UHFFFAOYSA-N 0.000 title claims abstract description 46
- 238000010189 synthetic method Methods 0.000 title description 4
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 36
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims abstract description 36
- FJKROLUGYXJWQN-UHFFFAOYSA-N 4-hydroxybenzoic acid Chemical compound OC(=O)C1=CC=C(O)C=C1 FJKROLUGYXJWQN-UHFFFAOYSA-N 0.000 claims abstract description 32
- 238000002425 crystallisation Methods 0.000 claims abstract description 28
- 230000008025 crystallization Effects 0.000 claims abstract description 28
- 239000012065 filter cake Substances 0.000 claims abstract description 25
- 238000003756 stirring Methods 0.000 claims abstract description 24
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 24
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims abstract description 22
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 22
- 238000006243 chemical reaction Methods 0.000 claims abstract description 19
- 238000001914 filtration Methods 0.000 claims abstract description 19
- 238000000034 method Methods 0.000 claims abstract description 17
- 229940090248 4-hydroxybenzoic acid Drugs 0.000 claims abstract description 16
- 238000005070 sampling Methods 0.000 claims abstract description 14
- 238000001816 cooling Methods 0.000 claims abstract description 12
- 239000012043 crude product Substances 0.000 claims abstract description 12
- 229960000583 acetic acid Drugs 0.000 claims abstract description 11
- 239000012362 glacial acetic acid Substances 0.000 claims abstract description 11
- 238000010438 heat treatment Methods 0.000 claims abstract description 11
- 230000002194 synthesizing effect Effects 0.000 claims abstract description 11
- APUPEJJSWDHEBO-UHFFFAOYSA-P ammonium molybdate Chemical compound [NH4+].[NH4+].[O-][Mo]([O-])(=O)=O APUPEJJSWDHEBO-UHFFFAOYSA-P 0.000 claims abstract description 10
- 229940010552 ammonium molybdate Drugs 0.000 claims abstract description 10
- 235000018660 ammonium molybdate Nutrition 0.000 claims abstract description 10
- 239000011609 ammonium molybdate Substances 0.000 claims abstract description 10
- 238000001035 drying Methods 0.000 claims abstract description 10
- 239000012295 chemical reaction liquid Substances 0.000 claims abstract description 7
- 239000007787 solid Substances 0.000 claims abstract description 6
- 229960000443 hydrochloric acid Drugs 0.000 claims abstract description 5
- 239000000047 product Substances 0.000 claims description 21
- 238000001514 detection method Methods 0.000 claims description 13
- 238000004811 liquid chromatography Methods 0.000 claims description 8
- 239000000203 mixture Substances 0.000 claims description 7
- 229960002163 hydrogen peroxide Drugs 0.000 claims description 6
- 239000002994 raw material Substances 0.000 abstract description 8
- 238000003786 synthesis reaction Methods 0.000 abstract description 7
- 230000015572 biosynthetic process Effects 0.000 abstract description 5
- 238000001308 synthesis method Methods 0.000 abstract description 5
- YNWKEXMSQQUMEL-UHFFFAOYSA-N 2-chloro-4-(trifluoromethyl)phenol Chemical compound OC1=CC=C(C(F)(F)F)C=C1Cl YNWKEXMSQQUMEL-UHFFFAOYSA-N 0.000 abstract description 4
- 238000002386 leaching Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000000543 intermediate Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000004321 preservation Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/347—Preparation of carboxylic acids or their salts, halides or anhydrides by reactions not involving formation of carboxyl groups
- C07C51/363—Preparation of carboxylic acids or their salts, halides or anhydrides by reactions not involving formation of carboxyl groups by introduction of halogen; by substitution of halogen atoms by other halogen atoms
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a method for synthesizing 3-chloro-4-hydroxybenzoic acid, which belongs to the technical field of chemical synthesis and comprises the following steps: adding glacial acetic acid into a reaction kettle, stirring and adding 4-hydroxybenzoic acid, ammonium molybdate and hydrochloric acid, controlling the temperature to be 10-15 ℃, dropwise adding hydrogen peroxide, standing, and sampling and detecting to obtain a reaction solution; carrying out centrifugal filtration on the reaction liquid, putting methanol and water into a crystallization kettle, then putting the obtained filter cake, stirring to completely dissolve the solid, cooling, keeping the temperature, stirring, and carrying out centrifugal filtration to obtain a primary crystallization crude product; putting methanol and water into a crystallization kettle, putting all primary crystallization crude products, heating and stirring, cooling, carrying out centrifugal filtration, and sampling and detecting filter cakes; drying under reduced pressure; the price of the main raw material 4-hydroxybenzoic acid in the invention is far lower than that of the main raw material 3-chloro-4-hydroxy trifluoromethyl benzene in the prior art, thereby reducing the synthesis cost; solves the problem of higher cost of the existing synthesis method of 3-chloro-4-hydroxybenzoic acid.
Description
Technical Field
The invention relates to the technical field of chemical synthesis, in particular to a synthetic method of 3-chloro-4-hydroxybenzoic acid.
Background
The appearance of the 3-chloro-4-hydroxybenzoic acid is light yellow powder, and the melting point of the pure product is 171-173 ℃. It is easily dissolved in hot water and absorbed moisture. Preferably storing in a sealed container, and placing in a cool, ventilated and dry place. Chemical intermediates for use in pharmaceutical synthesis. At present, 3-chloro-4-hydroxybenzoic acid is prepared by reacting 3-chloro-4-hydroxytrifluoromethylbenzene as a raw material with alkaline water, and the cost is high.
Disclosure of Invention
The invention provides a method for synthesizing 3-chloro-4-hydroxybenzoic acid to solve the technical problems.
In order to solve the technical problem, the following technical scheme is adopted:
the synthesis method of the 3-chloro-4-hydroxybenzoic acid comprises the following steps:
adding glacial acetic acid into a reaction kettle, starting stirring, adding 4-hydroxybenzoic acid, adding ammonium molybdate, adding hydrochloric acid, controlling the temperature to be 10-15 ℃, starting dropwise adding hydrogen peroxide, standing for 7 hours at 10-15 ℃ after dropwise adding, starting sampling detection, and stopping reaction when the main product is more than or equal to 87% to obtain a reaction solution;
carrying out centrifugal filtration on the reaction liquid to obtain a filter cake, putting methanol and water into a crystallization kettle, then putting the obtained filter cake, heating to 70-75 ℃ under stirring to completely dissolve solids, cooling to 20 +/-2 ℃ within 2-3 hours, carrying out heat preservation and stirring for 0.5 hour, and carrying out centrifugal filtration to obtain a primary crystallization crude product;
Putting methanol and water into a crystallization kettle, putting all primary crystallization crude products into the crystallization kettle again, heating the mixture to 40-45 ℃, stirring the mixture for 0.5 hour at the temperature, cooling the mixture to 20-25 ℃, performing centrifugal filtration, sampling and detecting filter cakes, and determining that the product is qualified when the content of the main product is more than or equal to 98 percent, and recrystallizing again when the content of the main product is less than 98 percent;
drying under reduced pressure.
As a further scheme of the invention: the mass ratio of the glacial acetic acid, the 4-hydroxybenzoic acid, the hydrochloric acid, the hydrogen peroxide and the ammonium molybdate is 220-230: 149-151: 163-167: 105.1-106.1: 1.1.
as a further scheme of the invention: the mass ratio of the glacial acetic acid to the 4-hydroxybenzoic acid to the hydrochloric acid to the hydrogen peroxide to the ammonium molybdate is 225: 150: 165: 105.6: 1.1.
as a further scheme of the invention: and in the process of dropwise adding hydrogen peroxide, when the temperature is not less than 20 ℃, stopping dropwise adding, restarting dropwise adding when the temperature is reduced to 10-15 ℃, and standing for 7 hours at 10-15 ℃ after dropwise adding.
As a further scheme of the invention: after dropwise adding hydrogen peroxide and standing for 7 hours, sampling is started, and liquid chromatography detection is adopted.
As a further scheme of the invention: and (3) carrying out centrifugal filtration on the reaction liquid to obtain a filter cake, and leaching the filter cake with water before putting the filter cake into a crystallization kettle.
As a further scheme of the invention: the reduced pressure drying comprises the following steps: drying under reduced pressure at 70-80 deg.C until the water content is less than 0.5%, and making it qualified.
Compared with the prior art, the invention has the beneficial effects that: the invention provides a method for synthesizing 3-chloro-4-hydroxybenzoic acid, which uses 4-hydroxybenzoic acid as a main raw material, has simple synthesis process, the price of the 4-hydroxybenzoic acid is far lower than that of 3-chloro-4-hydroxy trifluoromethyl benzene which is the main raw material in the prior art, and the synthesis cost is reduced.
Detailed Description
Example 1
The synthesis method of the 3-chloro-4-hydroxybenzoic acid comprises the following steps:
adding 225kg of glacial acetic acid into a reaction kettle, starting stirring, adding 150kg of 4-hydroxybenzoic acid, 1.1kg of ammonium molybdate, 165kg of hydrochloric acid, controlling the temperature to be 10 ℃, starting to dropwise add 105.6kg of hydrogen peroxide with the mass fraction of 35%, stopping dropwise adding when the temperature is not less than 20 ℃ in the process of dropwise adding the hydrogen peroxide, restarting dropwise adding when the temperature is reduced to 10 ℃, standing for 7 hours at 10 ℃ after dropwise adding, starting sampling detection, adopting liquid chromatography for detection, and stopping reaction when the main product is not less than 87% to obtain a reaction solution;
carrying out centrifugal filtration on the reaction liquid to obtain a filter cake, leaching the filter cake with 150kg of water, putting 120kg of methanol and 250kg of water into a crystallization kettle, then putting the leached filter cake, heating to 70 ℃ under stirring to completely dissolve solids, cooling to 20 ℃ within 2.5 hours, keeping the temperature and stirring for 0.5 hour, and carrying out centrifugal filtration to obtain a primary crystallization crude product;
Putting 180kg of methanol and 390kg of water into a crystallization kettle, putting all primary crystallization crude products again, heating to 40 ℃, stirring for 0.5 hour at the temperature, cooling to 20 ℃, performing centrifugal filtration, sampling and detecting filter cakes, and performing liquid chromatography detection to obtain qualified products when the content of the main products is more than or equal to 98 percent, and recrystallizing when the content of the main products is less than 98 percent;
drying at 75 deg.C under reduced pressure until the water content is less than 0.5%.
Example 2
The synthesis method of the 3-chloro-4-hydroxybenzoic acid comprises the following steps:
adding 220kg of glacial acetic acid into a reaction kettle, starting stirring, adding 149kg of 4-hydroxybenzoic acid, 1.0kg of ammonium molybdate, 163kg of hydrochloric acid, controlling the temperature to be 10 ℃, starting to dropwise add 105.1kg of hydrogen peroxide with the mass fraction of 35%, stopping dropwise adding when the temperature is not lower than 20 ℃ in the process of dropwise adding the hydrogen peroxide, restarting dropwise adding when the temperature is reduced to 10 ℃, standing for 7 hours at 10 ℃ after dropwise adding, starting sampling detection, adopting liquid chromatography for detection, and stopping reaction when the main product is not lower than 87% to obtain a reaction solution;
carrying out centrifugal filtration on the reaction liquid to obtain a filter cake, leaching the filter cake with 150kg of water, putting 120kg of methanol and 250kg of water into a crystallization kettle, then putting the leached filter cake, heating to 70 ℃ under stirring to completely dissolve solids, cooling to 18 ℃ within 2 hours, keeping the temperature and stirring for 0.5 hour, and carrying out centrifugal filtration to obtain a primary crystallization crude product;
Putting 180kg of methanol and 390kg of water into a crystallization kettle, putting all primary crystallization crude products again, heating to 40 ℃, stirring for 0.5 hour at the temperature, cooling to 20 ℃, performing centrifugal filtration, sampling and detecting filter cakes, and performing liquid chromatography detection to obtain a qualified product when the content of a main product is more than or equal to 98 percent, and recrystallizing again when the content of the main product is less than 98 percent;
drying under reduced pressure at 70 deg.C until the water content is less than 0.5%.
Example 3
The synthesis method of the 3-chloro-4-hydroxybenzoic acid comprises the following steps:
adding 230kg of glacial acetic acid into a reaction kettle, starting stirring, adding 151kg of 4-hydroxybenzoic acid, 1.2kg of ammonium molybdate, 167kg of hydrochloric acid, controlling the temperature to be 15 ℃, starting to dropwise add 101.1kg of 35% hydrogen peroxide, stopping dropwise adding when the temperature is not less than 20 ℃ in the process of dropwise adding the hydrogen peroxide, restarting dropwise adding when the temperature is reduced to 15 ℃, standing for 7 hours at 15 ℃ after dropwise adding, starting sampling detection, adopting liquid chromatography for detection, and stopping reaction when a main product is not less than 87% to obtain a reaction solution;
carrying out centrifugal filtration on the reaction liquid to obtain a filter cake, leaching the filter cake with 150kg of water, putting 120kg of methanol and 250kg of water into a crystallization kettle, then putting the leached filter cake, heating to 75 ℃ under stirring to completely dissolve solids, cooling to 22 ℃ within 3 hours, keeping the temperature and stirring for 0.5 hour, and carrying out centrifugal filtration to obtain a primary crystallization crude product;
Putting 180kg of methanol and 390kg of water into a crystallization kettle, putting all primary crystallization crude products again, heating to 45 ℃, stirring for 0.5 hour at the temperature, cooling to 25 ℃, performing centrifugal filtration, sampling and detecting filter cakes, and performing liquid chromatography detection to obtain qualified products when the content of the main products is more than or equal to 98 percent, and recrystallizing when the content of the main products is less than 98 percent;
drying under reduced pressure at 80 deg.C until the water content is less than 0.5%.
In the embodiment of the invention, the reaction formula in the synthetic method of the 3-chloro-4-hydroxybenzoic acid is as follows:
in summary, the following steps: the invention provides a method for synthesizing 3-chloro-4-hydroxybenzoic acid, wherein 4-hydroxybenzoic acid, glacial acetic acid, hydrochloric acid and hydrogen peroxide are used as raw materials to prepare 3-chloro-4-hydroxybenzoic acid, the 4-hydroxybenzoic acid is used as the main raw material in the method, the price of the 4-hydroxybenzoic acid is far lower than that of 3-chloro-4-hydroxytrifluoromethylbenzene which is the main raw material in the prior art, and the synthesis cost is reduced.
Claims (7)
- The method for synthesizing the 1.3-chloro-4-hydroxybenzoic acid is characterized by comprising the following steps:adding glacial acetic acid into a reaction kettle, starting stirring, adding 4-hydroxybenzoic acid, adding ammonium molybdate, adding hydrochloric acid, controlling the temperature to be 10-15 ℃, starting dropwise adding hydrogen peroxide, standing for 7 hours at 10-15 ℃ after dropwise adding, starting sampling detection, and stopping reaction when the main product is more than or equal to 87% to obtain a reaction solution;Carrying out centrifugal filtration on the reaction liquid to obtain a filter cake, putting methanol and water into a crystallization kettle, then putting the obtained filter cake, heating to 70-75 ℃ under stirring to completely dissolve solids, cooling to 20 +/-2 ℃ within 2-3 hours, keeping the temperature and stirring for 0.5 hour, and carrying out centrifugal filtration to obtain a primary crystallization crude product;putting methanol and water into a crystallization kettle, putting all primary crystallization crude products into the crystallization kettle again, heating the mixture to 40-45 ℃, stirring the mixture for 0.5 hour at the temperature, cooling the mixture to 20-25 ℃, performing centrifugal filtration, sampling and detecting filter cakes, and determining that the product is qualified when the content of the main product is more than or equal to 98 percent, and recrystallizing again when the content of the main product is less than 98 percent;drying under reduced pressure.
- 2. The method for synthesizing 3-chloro-4-hydroxybenzoic acid according to claim 1, wherein the mass ratio of glacial acetic acid, 4-hydroxybenzoic acid, hydrochloric acid, hydrogen peroxide and ammonium molybdate is 220-: 149-151: 163-167: 105.1-106.1: 1.1.
- 3. the method for synthesizing 3-chloro-4-hydroxybenzoic acid according to claim 2, wherein the mass ratio of glacial acetic acid, 4-hydroxybenzoic acid, hydrochloric acid, hydrogen peroxide and ammonium molybdate is 225: 150: 165: 105.6: 1.1.
- 4. the method for synthesizing 3-chloro-4-hydroxybenzoic acid according to claim 1, wherein the dropwise addition of hydrogen peroxide is stopped when the temperature is not lower than 20 ℃, and is resumed when the temperature drops to 10 to 15 ℃, and after the completion of the dropwise addition, the mixture is allowed to stand at 10 to 15 ℃ for 7 hours.
- 5. The method for synthesizing 3-chloro-4-hydroxybenzoic acid according to claim 1, wherein after dropping hydrogen peroxide and standing for 7 hours, sampling is started and liquid chromatography is used for detection.
- 6. The method of synthesizing 3-chloro-4-hydroxybenzoic acid according to claim 1, wherein the reaction solution is centrifuged to obtain a filter cake, and the filter cake is rinsed with water before being put into the crystallization vessel.
- 7. The method for synthesizing 3-chloro-4-hydroxybenzoic acid according to claim 1, wherein the reduced pressure drying is: drying under reduced pressure at 70-80 deg.C until the water content is less than 0.5%.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210198979.2A CN114671753A (en) | 2022-03-02 | 2022-03-02 | Synthetic method of 3-chloro-4-hydroxybenzoic acid |
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| CN202210198979.2A CN114671753A (en) | 2022-03-02 | 2022-03-02 | Synthetic method of 3-chloro-4-hydroxybenzoic acid |
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| CN202210198979.2A Pending CN114671753A (en) | 2022-03-02 | 2022-03-02 | Synthetic method of 3-chloro-4-hydroxybenzoic acid |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102112426A (en) * | 2008-08-05 | 2011-06-29 | 巴斯夫欧洲公司 | Process for the preparation of 4-bromophenyl derivatives |
| CN109503499A (en) * | 2018-12-30 | 2019-03-22 | 南京天越星生物技术有限公司 | A kind of Fan get Ta Ni intermediate and preparation method thereof |
-
2022
- 2022-03-02 CN CN202210198979.2A patent/CN114671753A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102112426A (en) * | 2008-08-05 | 2011-06-29 | 巴斯夫欧洲公司 | Process for the preparation of 4-bromophenyl derivatives |
| CN109503499A (en) * | 2018-12-30 | 2019-03-22 | 南京天越星生物技术有限公司 | A kind of Fan get Ta Ni intermediate and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| L. G. DERKACH ET AL.: "Banana-Shaped Liquid Crystals Based on 2, 7-Dihydroxynaphthalene Derivatives", 《RUSSIAN JOURNAL OF GENERAL CHEMISTRY》, vol. 85, no. 3, pages 577 - 583, XP035483853, DOI: 10.1134/S1070363215030081 * |
| SUDIP MUKHOPADHYAY ET AL.: "Highly Selective Oxidative Monochlorination To Synthesize Organic Intermediates: 2-Chlorotoluene, 2-Chloroaniline, 2-Chlorophenol, and 2-Chloro-4-methylphenol", 《ORGANIC PROCESS RESEARCH & DEVELOPMENT》, vol. 3, pages 196 - 200 * |
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