CN113620797A - Method for preparing 2, 4-dichloroacetophenone - Google Patents
Method for preparing 2, 4-dichloroacetophenone Download PDFInfo
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- CN113620797A CN113620797A CN202110907644.9A CN202110907644A CN113620797A CN 113620797 A CN113620797 A CN 113620797A CN 202110907644 A CN202110907644 A CN 202110907644A CN 113620797 A CN113620797 A CN 113620797A
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- dichloroacetophenone
- temperature
- oil layer
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- dichlorobenzene
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- XMCRWEBERCXJCH-UHFFFAOYSA-N 1-(2,4-dichlorophenyl)ethanone Chemical compound CC(=O)C1=CC=C(Cl)C=C1Cl XMCRWEBERCXJCH-UHFFFAOYSA-N 0.000 title claims abstract description 47
- 238000000034 method Methods 0.000 title claims abstract description 42
- 238000005406 washing Methods 0.000 claims abstract description 19
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 15
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 claims abstract description 15
- 150000001408 amides Chemical class 0.000 claims abstract description 13
- FXXACINHVKSMDR-UHFFFAOYSA-N acetyl bromide Chemical compound CC(Br)=O FXXACINHVKSMDR-UHFFFAOYSA-N 0.000 claims abstract description 10
- 239000012752 auxiliary agent Substances 0.000 claims abstract description 9
- 238000006243 chemical reaction Methods 0.000 claims abstract description 9
- 238000003756 stirring Methods 0.000 claims abstract description 9
- 230000018044 dehydration Effects 0.000 claims abstract description 8
- 238000006297 dehydration reaction Methods 0.000 claims abstract description 8
- 239000000203 mixture Substances 0.000 claims abstract description 7
- OCJBOOLMMGQPQU-UHFFFAOYSA-N 1,4-dichlorobenzene Chemical compound ClC1=CC=C(Cl)C=C1 OCJBOOLMMGQPQU-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229940117389 dichlorobenzene Drugs 0.000 claims abstract description 4
- 238000002156 mixing Methods 0.000 claims abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 19
- ZPQOPVIELGIULI-UHFFFAOYSA-N 1,3-dichlorobenzene Chemical compound ClC1=CC=CC(Cl)=C1 ZPQOPVIELGIULI-UHFFFAOYSA-N 0.000 claims description 13
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 9
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 claims description 3
- VEFXTGTZJOWDOF-UHFFFAOYSA-N benzene;hydrate Chemical compound O.C1=CC=CC=C1 VEFXTGTZJOWDOF-UHFFFAOYSA-N 0.000 claims description 3
- 238000005903 acid hydrolysis reaction Methods 0.000 claims 1
- 230000032798 delamination Effects 0.000 claims 1
- 239000002994 raw material Substances 0.000 abstract description 5
- 230000000694 effects Effects 0.000 abstract description 4
- 239000003153 chemical reaction reagent Substances 0.000 abstract description 3
- 238000002360 preparation method Methods 0.000 abstract description 3
- 238000004090 dissolution Methods 0.000 abstract description 2
- 239000000376 reactant Substances 0.000 abstract description 2
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000003786 synthesis reaction Methods 0.000 description 4
- WETWJCDKMRHUPV-UHFFFAOYSA-N acetyl chloride Chemical compound CC(Cl)=O WETWJCDKMRHUPV-UHFFFAOYSA-N 0.000 description 3
- 239000012346 acetyl chloride Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000007062 hydrolysis Effects 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 238000007086 side reaction Methods 0.000 description 2
- XMAYWYJOQHXEEK-OZXSUGGESA-N (2R,4S)-ketoconazole Chemical compound C1CN(C(=O)C)CCN1C(C=C1)=CC=C1OC[C@@H]1O[C@@](CN2C=NC=C2)(C=2C(=CC(Cl)=CC=2)Cl)OC1 XMAYWYJOQHXEEK-OZXSUGGESA-N 0.000 description 1
- 239000005760 Difenoconazole Substances 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 230000000844 anti-bacterial effect Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- BQYJATMQXGBDHF-UHFFFAOYSA-N difenoconazole Chemical compound O1C(C)COC1(C=1C(=CC(OC=2C=CC(Cl)=CC=2)=CC=1)Cl)CN1N=CN=C1 BQYJATMQXGBDHF-UHFFFAOYSA-N 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 229960004125 ketoconazole Drugs 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000000575 pesticide Substances 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 239000003053 toxin Substances 0.000 description 1
- 231100000765 toxin Toxicity 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/45—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by condensation
- C07C45/455—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by condensation with carboxylic acids or their derivatives
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/78—Separation; Purification; Stabilisation; Use of additives
- C07C45/81—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
- C07C45/82—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The application discloses a method for preparing 2, 4-dichloroacetophenone, which comprises the following steps: s1: mixing dichlorobenzene, aluminum trichloride and an amide auxiliary agent and stirring; s2: when the stirring temperature is raised to 40 ℃, acetyl bromide is dripped into the mixture for reaction to obtain 2, 4-dichloroacetophenone synthetic solution; s3: adding the 2, 4-dichloroacetophenone synthetic solution obtained in the step 2 into hydrochloric acid for acidolysis and layering, and separating and washing an oil layer after layering; s4: dehydrating the washed oil layer in a vacuum environment, and removing light when the temperature is raised to 98 ℃; s5: rectifying the residue after dehydration and lightness removal to obtain the 2, 4-dichloroacetophenone. This application is through adopting acetyl bromide as the raw materials, can effectively reduce electrophilic reagent's activity, and further can improve the yield of product. Meanwhile, the amide auxiliary agent is added in the preparation process of the 2, 4-dichloroacetophenone synthetic solution, so that the dissolution of aluminum trichloride is promoted, the contact area of reactants is increased, and the reaction efficiency is greatly improved.
Description
Technical Field
The application relates to the field of fine chemical engineering, in particular to a method for preparing 2, 4-dichloroacetophenone.
Background
The 2, 4-dichloroacetophenone is an important pesticide and a medical intermediate, and is mainly used for synthesizing bactericidal medicaments such as difenoconazole, ketoconazole and the like.
In 2008, a paper entitled "research on 2, 4-dichloroacetophenone synthesis process" was published by yazhen of the institute of technology and training, jiangsu province, and the like in chemical engineers, and the paper adopts m-dichlorobenzene, acetic anhydride and aluminum trichloride as raw materials and obtains the 2, 4-dichloroacetophenone by the processes of synthesis, hydrolysis, extraction, washing, lightness removal and rectification, and the yield is 81.8%. The process uses acetic anhydride which is easy to prepare toxin as a raw material, and has the advantages of complex steps and low yield.
In 2021, Jiangxi Yongtong scientific and technological Co., Ltd applied for a synthesis method of 2, 4-dichloroacetophenone (CN112500277A), which uses m-dichlorobenzene, acetyl chloride and modified aluminum trichloride as raw materials and obtains the 2, 4-dichloroacetophenone through the procedures of synthesis, hydrolysis, extraction, distillation and the like, the process increases the activity and reaction rate of the catalyst, but the highest yield of the process is only 83.77% due to the characteristics of high activity of electrophilic reagent acetyl chloride and more side reactions. Therefore, there is a need for a method for preparing 2, 4-dichloroacetophenone which solves the above problems.
Disclosure of Invention
The application provides a method for preparing 2, 4-dichloroacetophenone, and solves the problems of low preparation yield and poor purity of 2, 4-dichloroacetophenone in the prior art.
The application provides a method for preparing 2, 4-dichloroacetophenone, which comprises the following steps:
s1: mixing dichlorobenzene, aluminum trichloride and an amide auxiliary agent and stirring;
s2: when the stirring temperature is raised to 40 ℃, acetyl bromide is dripped into the mixture for reaction, the dripping process lasts for 2 to 3 hours, the temperature is raised to 100 ℃, then the temperature is kept for 1 to 2 hours, and the 2, 4-dichloroacetophenone synthetic solution is obtained when the temperature is lowered to 50 ℃;
s3: adding the 2, 4-dichloroacetophenone synthetic solution obtained in the step 2 into hydrochloric acid for acidolysis and layering, separating an oil layer after layering, washing the separated oil layer for a plurality of times until the pH value is 6-7 to obtain a washed oil layer, wherein the washed oil layer contains water and m-dichlorobenzene;
s4: dehydrating the washed oil layer in a vacuum environment, and removing light when the temperature is raised to 98 ℃;
s5: rectifying the residue after dehydration and lightness removal to obtain the 2, 4-dichloroacetophenone.
Further, in the method for preparing 2, 4-dichloroacetophenone, water in an oil layer after water washing is separated in the dehydration process in the step 4, and m-dichlorobenzene in the oil layer after water washing is separated in the light component removal process in the step 4.
Further, the method for preparing 2, 4-dichloroacetophenone is characterized in that the molar ratio of acetyl bromide, m-dichlorobenzene and aluminum trichloride in the step 1 is 1: 1.1-1.3: 1.05-1.2.
Further, the hydrochloric acid concentration in the step 2 is 5 percent.
Further, in the method for preparing 2, 4-dichloroacetophenone, the acidolysis layering temperature in the step 3 is 50-80 ℃.
Further, the temperature of the water washing process in the step 3 is 40-60 ℃.
Further, the method for preparing the 2, 4-dichloroacetophenone is characterized in that the amide auxiliary agent in the step 1 is one or a mixture of N, N-dimethylformamide and N, N-dimethylacetamide, and the molar ratio of the amide auxiliary agent to aluminum trichloride is 10-5: 1.
According to the technical scheme, the method for preparing the 2, 4-dichloroacetophenone is provided, acetyl bromide is used as a raw material, so that the activity of an electrophilic reagent can be effectively reduced, and the yield of the product can be further improved. Meanwhile, the amide auxiliary agent is added in the preparation process of the 2, 4-dichloroacetophenone synthetic solution, so that the dissolution of aluminum trichloride is promoted, the contact area of reactants is increased, and the reaction efficiency is greatly improved. The product yield is improved from the traditional 81 percent to 89 percent. The yield is improved by 8 percent compared with the traditional acetyl chloride production process, and the reaction time is also reduced by 1 to 2 hours. The method has the characteristics of simple synthesis process, high product yield, less side reaction and short reaction time in the application process, and is easy to prepare the high-content 2, 4-dichloroacetophenone.
Drawings
In order to more clearly illustrate the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without any creative effort.
FIG. 1 is a process flow diagram of the present application;
FIG. 2 is a schematic diagram of the chemical reaction equations of the present application.
Detailed Description
In order to make those skilled in the art better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.
See FIGS. 1-2
According to the technical scheme, the method for preparing the 2, 4-dichloroacetophenone comprises the following steps:
s1: mixing dichlorobenzene, aluminum trichloride and an amide auxiliary agent and stirring;
s2: when the stirring temperature is raised to 40 ℃, acetyl bromide is dripped into the mixture for reaction, the dripping process lasts for 2 to 3 hours, the temperature is raised to 100 ℃, then the temperature is kept for 1 to 2 hours, and the 2, 4-dichloroacetophenone synthetic solution is obtained when the temperature is lowered to 50 ℃;
s3: adding the 2, 4-dichloroacetophenone synthetic solution obtained in the step 2 into hydrochloric acid for acidolysis and layering, separating an oil layer after layering, washing the separated oil layer for a plurality of times until the pH value is 6-7 to obtain a washed oil layer, wherein the washed oil layer contains water and m-dichlorobenzene;
s4: dehydrating the washed oil layer in a vacuum environment, and removing light when the temperature is raised to 98 ℃;
s5: rectifying the residue after dehydration and lightness removal to obtain the 2, 4-dichloroacetophenone.
Preferably, in the method for preparing 2, 4-dichloroacetophenone, the dehydration process in the step 4 separates water in an oil layer after water washing, and the lightness-removing process in the step 4 separates m-dichlorobenzene in the oil layer after water washing.
Preferably, the method for preparing 2, 4-dichloroacetophenone has the molar ratio of acetyl bromide, m-dichlorobenzene and aluminum trichloride in the step 1 of 1: 1.1-1.3: 1.05-1.2.
Preferably, the hydrochloric acid concentration in the step 2 is 5 percent.
Preferably, in the step 3, the acidolysis layering temperature is 50-80 ℃.
Preferably, in the step 3, the temperature of the water washing process is 40-60 ℃.
Preferably, the method for preparing the 2, 4-dichloroacetophenone is characterized in that the amide assistant in the step 1 is one or a mixture of N, N-dimethylformamide and N, N-dimethylacetamide, and the molar ratio of the amide assistant to aluminum trichloride is 10-5: 1.
In the present application, preferably, m-dichlorobenzene (106.4g, 0.72mol), aluminum trichloride (89.5g, 0.66mol) and an amide auxiliary agent (9.7g, 0.132mol) were put into a four-neck flask equipped with a stirrer, a thermometer and a condenser, and the temperature was raised to 40 ℃ by stirring, and acetyl bromide (74.2g, 0.6mol) was added dropwise to the four-neck flask over about 2.5 hours. The temperature is raised to 100 ℃, the temperature is kept for 1.5 hours, and then the temperature is reduced to 50 ℃, thus obtaining 229.5g of 2, 4-dichloroacetophenone synthetic solution.
The 2, 4-dichloroacetophenone synthetic solution was transferred to a dropping funnel, and was dropped into another four-necked flask containing 850g of 5% diluted hydrochloric acid, with the reaction temperature being controlled to about 60 ℃. After the addition, the layers were separated. Putting the oil layer after acidolysis into a kettle, washing with 60g of water for several times, and controlling the washing temperature to be 45-50 ℃ during the washing. And after layering, stopping the water washing process when the pH of the last water layer is measured to be 6-7, and treating the washed oil layer.
And (3) putting the oil layer after water washing into a four-mouth bottle, controlling the vacuum of a system to be about 15mmHg, heating for dehydration, switching a material receiving bottle, and continuously heating to evaporate m-dichlorobenzene. And switching the four-mouth bottle to a rectification system at the maximum temperature of 128 ℃, controlling the absolute pressure of the system to be 8mmHg, and adjusting the reflux ratio to collect a 2, 4-dichloroacetophenone refined product. The temperature of the kettle bottom is not more than 150 ℃ at most. 102.8g of a product was obtained (content: 99.1%, yield: 89.8%).
Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims.
It will be understood that the present application is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The above-described embodiments of the present application do not limit the scope of the present application.
Claims (7)
1. A method for preparing 2, 4-dichloroacetophenone is characterized by comprising the following steps:
s1: mixing dichlorobenzene, aluminum trichloride and an amide auxiliary agent and stirring;
s2: when the stirring temperature is raised to 40 ℃, acetyl bromide is dripped into the mixture for reaction, the dripping process lasts for 2 to 3 hours, the temperature is raised to 100 ℃, then the temperature is kept for 1 to 2 hours, and the 2, 4-dichloroacetophenone synthetic solution is obtained when the temperature is lowered to 50 ℃;
s3: adding the 2, 4-dichloroacetophenone synthetic solution obtained in the step 2 into hydrochloric acid for acidolysis and layering, separating an oil layer after layering, washing the separated oil layer for a plurality of times until the pH value is 6-7 to obtain a washed oil layer, wherein the washed oil layer contains water and m-dichlorobenzene;
s4: dehydrating the washed oil layer in a vacuum environment, and removing light when the temperature is raised to 98 ℃;
s5: rectifying the residue after dehydration and lightness removal to obtain the 2, 4-dichloroacetophenone.
2. The method for preparing 2, 4-dichloroacetophenone according to claim 1, characterized in that the dehydration process in step 4 separates water from the oil layer after water washing, and the lightness-removing process in step 4 separates m-dichlorobenzene from the oil layer after water washing.
3. The method for preparing 2, 4-dichloroacetophenone according to claim 1, characterized in that the molar ratio of acetyl bromide, m-dichlorobenzene and aluminum trichloride in step 1 is 1: 1.1-1.3: 1.05-1.2.
4. The method for preparing 2, 4-dichloroacetophenone according to claim 1, characterized in that the hydrochloric acid concentration in step 2 is 5%.
5. The method for preparing 2, 4-dichloroacetophenone according to claim 1, wherein the temperature for acid hydrolysis delamination in step 3 is 50-80 ℃.
6. The method for preparing 2, 4-dichloroacetophenone according to claim 1, characterized in that the temperature of the water washing process in step 3 is 40-60 ℃.
7. The method for preparing 2, 4-dichloroacetophenone according to claim 1, characterized in that the amide assistant in step 1 is one or a mixture of N, N-dimethylformamide and N, N-dimethylacetamide, and the molar ratio of the amide assistant to aluminum trichloride is 10-5: 1.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110907644.9A CN113620797A (en) | 2021-08-09 | 2021-08-09 | Method for preparing 2, 4-dichloroacetophenone |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110907644.9A CN113620797A (en) | 2021-08-09 | 2021-08-09 | Method for preparing 2, 4-dichloroacetophenone |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1135358A (en) * | 1967-06-01 | 1968-12-04 | Shell Int Research | Process for the preparation of 2,4-disubstituted phenyl ketones |
| CN102675073A (en) * | 2012-05-24 | 2012-09-19 | 江苏隆昌化工有限公司 | Method for preparing 2, 4-dichloroacetophenone |
| CN110668948A (en) * | 2019-10-28 | 2020-01-10 | 苏州敬业医药化工有限公司 | Preparation method of 4-chloro-2-fluoro-5-nitroacetophenone |
| CN110922322A (en) * | 2019-11-01 | 2020-03-27 | 江苏隆昌化工有限公司 | Clean production method for improving reaction yield of 2, 4-dichloroacetophenone |
-
2021
- 2021-08-09 CN CN202110907644.9A patent/CN113620797A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1135358A (en) * | 1967-06-01 | 1968-12-04 | Shell Int Research | Process for the preparation of 2,4-disubstituted phenyl ketones |
| CN102675073A (en) * | 2012-05-24 | 2012-09-19 | 江苏隆昌化工有限公司 | Method for preparing 2, 4-dichloroacetophenone |
| CN110668948A (en) * | 2019-10-28 | 2020-01-10 | 苏州敬业医药化工有限公司 | Preparation method of 4-chloro-2-fluoro-5-nitroacetophenone |
| CN110922322A (en) * | 2019-11-01 | 2020-03-27 | 江苏隆昌化工有限公司 | Clean production method for improving reaction yield of 2, 4-dichloroacetophenone |
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