CN115784856B - Method for synthesizing 4,4' -dihalogenated benzophenone - Google Patents
Method for synthesizing 4,4' -dihalogenated benzophenone Download PDFInfo
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- CN115784856B CN115784856B CN202211402276.3A CN202211402276A CN115784856B CN 115784856 B CN115784856 B CN 115784856B CN 202211402276 A CN202211402276 A CN 202211402276A CN 115784856 B CN115784856 B CN 115784856B
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- oxalyl chloride
- hydrochloric acid
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- 238000000034 method Methods 0.000 title claims abstract description 25
- 230000002194 synthesizing effect Effects 0.000 title claims abstract description 9
- 150000008366 benzophenones Chemical class 0.000 title abstract description 13
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 55
- CTSLXHKWHWQRSH-UHFFFAOYSA-N oxalyl chloride Chemical compound ClC(=O)C(Cl)=O CTSLXHKWHWQRSH-UHFFFAOYSA-N 0.000 claims abstract description 44
- 238000006243 chemical reaction Methods 0.000 claims abstract description 29
- 150000001875 compounds Chemical class 0.000 claims abstract description 13
- 239000003054 catalyst Substances 0.000 claims abstract description 12
- 238000010438 heat treatment Methods 0.000 claims abstract description 5
- 238000006460 hydrolysis reaction Methods 0.000 claims description 17
- 239000012074 organic phase Substances 0.000 claims description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 16
- 239000012535 impurity Substances 0.000 claims description 9
- LSQARZALBDFYQZ-UHFFFAOYSA-N 4,4'-difluorobenzophenone Chemical compound C1=CC(F)=CC=C1C(=O)C1=CC=C(F)C=C1 LSQARZALBDFYQZ-UHFFFAOYSA-N 0.000 claims description 7
- 238000005406 washing Methods 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 5
- OKISUZLXOYGIFP-UHFFFAOYSA-N 4,4'-dichlorobenzophenone Chemical compound C1=CC(Cl)=CC=C1C(=O)C1=CC=C(Cl)C=C1 OKISUZLXOYGIFP-UHFFFAOYSA-N 0.000 claims description 4
- 229910021578 Iron(III) chloride Inorganic materials 0.000 claims description 2
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 claims description 2
- 239000003153 chemical reaction reagent Substances 0.000 abstract description 4
- 238000009776 industrial production Methods 0.000 abstract description 3
- 230000007062 hydrolysis Effects 0.000 description 8
- 238000005917 acylation reaction Methods 0.000 description 7
- 238000003756 stirring Methods 0.000 description 7
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 description 6
- 239000002253 acid Substances 0.000 description 5
- 239000003513 alkali Substances 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 150000003839 salts Chemical class 0.000 description 5
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 4
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 description 4
- YGYAWVDWMABLBF-UHFFFAOYSA-N Phosgene Chemical compound ClC(Cl)=O YGYAWVDWMABLBF-UHFFFAOYSA-N 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 239000012043 crude product Substances 0.000 description 3
- 239000003814 drug Substances 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- PYLWMHQQBFSUBP-UHFFFAOYSA-N monofluorobenzene Chemical compound FC1=CC=CC=C1 PYLWMHQQBFSUBP-UHFFFAOYSA-N 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- PASDCCFISLVPSO-UHFFFAOYSA-N benzoyl chloride Chemical class ClC(=O)C1=CC=CC=C1 PASDCCFISLVPSO-UHFFFAOYSA-N 0.000 description 2
- 229940079593 drug Drugs 0.000 description 2
- 229920006351 engineering plastic Polymers 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 239000012847 fine chemical Substances 0.000 description 2
- 231100000086 high toxicity Toxicity 0.000 description 2
- 208000024827 Alzheimer disease Diseases 0.000 description 1
- 238000005727 Friedel-Crafts reaction Methods 0.000 description 1
- 239000002841 Lewis acid Substances 0.000 description 1
- 206010039966 Senile dementia Diseases 0.000 description 1
- 230000010933 acylation Effects 0.000 description 1
- RWCCWEUUXYIKHB-UHFFFAOYSA-N benzophenone Chemical compound C=1C=CC=CC=1C(=O)C1=CC=CC=C1 RWCCWEUUXYIKHB-UHFFFAOYSA-N 0.000 description 1
- 239000012965 benzophenone Substances 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 230000002490 cerebral effect Effects 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- 239000012320 chlorinating reagent Substances 0.000 description 1
- 125000001309 chloro group Chemical group Cl* 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 238000005886 esterification reaction Methods 0.000 description 1
- 239000012065 filter cake Substances 0.000 description 1
- 238000002329 infrared spectrum Methods 0.000 description 1
- 150000007517 lewis acids Chemical class 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910001510 metal chloride Inorganic materials 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- SYSQUGFVNFXIIT-UHFFFAOYSA-N n-[4-(1,3-benzoxazol-2-yl)phenyl]-4-nitrobenzenesulfonamide Chemical class C1=CC([N+](=O)[O-])=CC=C1S(=O)(=O)NC1=CC=C(C=2OC3=CC=CC=C3N=2)C=C1 SYSQUGFVNFXIIT-UHFFFAOYSA-N 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000000575 pesticide Substances 0.000 description 1
- 229920006260 polyaryletherketone Polymers 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 230000024883 vasodilation Effects 0.000 description 1
Classifications
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- 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)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
The invention discloses a method for synthesizing 4,4' -dihalogenated benzophenone, which comprises the following steps: heating and reacting the compound shown in the formula (I) with oxalyl chloride under the action of a catalyst, and adding hydrochloric acid for reaction after the reaction to obtain a compound shown in the formula (II); wherein X is F or Cl. The invention can directly synthesize the 4,4' -dihalogenated benzophenone, the reaction route is simple to operate, environment-friendly, low in cost without expensive reagents, high in product yield and purity, safe and practical, and suitable for industrial production.
Description
Technical Field
The invention belongs to the field of fine chemical engineering, and in particular relates to a novel method for synthesizing 4,4' -dihalogenated benzophenone.
Background
4,4' -Dihalogenated benzophenone is used as a fine chemical intermediate, and the key monomer of new material special engineering plastic PAEK is synthesized by using various industries such as special engineering plastic, photoinitiator, medicine, pesticide and the like, for example, 4' -difluorobenzophenone and 4,4' -dichlorobenzophenone; can also be used as a medical intermediate, wherein 4,4' -difluorobenzophenone is a key intermediate for synthesizing a powerful cerebral vasodilation drug, namely, sibirizine hydrochloride, and a drug for treating senile dementia.
At present, the traditional synthesis methods of dihalobenzophenone include the following methods:
(1) Phosgene method: phosgene is one of the important methods for synthesizing benzophenone products, but phosgene is used as a chlorinating agent, so that the toxicity is high;
(2) Carbon tetrachloride method: because carbon tetrachloride is toxic and has large pollution, the carbon tetrachloride is basically forbidden;
(3) Friedel-crafts reaction: the halogenated aromatic hydrocarbon and halogenated benzoyl chloride react under the catalysis of Lewis acid.
The three methods (1) and (2) are easy to generate a large amount of isomers, have low yield, and the used chloro reagent has high toxicity and is basically not recommended to use; the method (3) needs to use halogenated benzoyl chloride, and generally needs to be synthesized separately, so that the method is relatively expensive and has relatively high cost.
Disclosure of Invention
The invention provides a novel method for synthesizing 4,4' -dihalobenzophenone by a one-step method on the basis of the prior art. The method has the advantages of simple operation, high product yield and purity, safety and practicality, and is suitable for industrial production.
The aim of the invention can be achieved by the following measures:
a method for synthesizing 4,4' -dihalobenzophenone, comprising the steps of: heating and reacting the compound shown in the formula (I) with oxalyl chloride under the action of a catalyst, and adding hydrochloric acid for reaction after the reaction to obtain a compound shown in the formula (II);
Wherein X is F or Cl.
The invention takes halogenated aromatic hydrocarbon and oxalyl chloride as raw materials, and the 4,4' -dihalogenated benzophenone can be prepared by simple reaction in the presence of a catalyst, and the chemical reaction route is as follows:
the reaction of the compound of formula (I) and oxalyl chloride is carried out in an anhydrous environment, and HCl gas generated in the reaction is absorbed by water to obtain hydrochloric acid solution, wherein the hydrochloric acid solution can be used in subsequent reactions or used for other purposes.
The invention relates to a specific process which comprises the following steps: mixing the structural halogenated aromatic hydrocarbon represented by the formula (I) with oxalyl chloride, heating to a certain temperature in the presence of a catalyst to perform an acylation reaction, adding an aqueous hydrochloric acid solution to perform hydrolysis after the reaction is finished, standing for layering after the hydrolysis reaction, removing a water layer, washing an obtained organic phase to remove impurities, cooling and crystallizing to obtain the 4,4' -dihalogenated benzophenone with the structure represented by the formula (II).
In the acylation reaction, the molar ratio of the compound of formula (I) to oxalyl chloride is 10-15:1, preferably 11-13:1.
In the acylation reaction, the molar ratio of the catalyst to oxalyl chloride is 1-4:1, preferably 2-3:1.
In the acylation reaction, the catalyst can be a metal chloride catalyst, and particularly AlCl 3、FeCl3, znCl 2 and the like are preferred.
The temperature of the acylation reaction is preferably 40 to 90 ℃, more preferably 50 to 70 ℃, and the time of the esterification reaction is preferably 4 to 6hr.
HCl gas generated in the acylation reaction is absorbed by water to obtain hydrochloric acid solution, which can be used for the next hydrolysis reaction.
In the hydrolysis reaction, the mass fraction of the hydrochloric acid solution is 5-37%, preferably 8-25%.
In the hydrolysis reaction, the volume-mass ratio of the hydrochloric acid solution to the oxalyl chloride is 1-5:1ml/g, preferably 3-4:1ml/g. The hydrolysis reaction temperature is 20-60 ℃, preferably 20-30 ℃ at normal temperature.
And (3) standing for layering after the hydrolysis reaction, removing a water layer, washing an obtained organic phase, removing impurities, and cooling for crystallization to obtain the compound shown in the formula (II).
The organic phase obtained by hydrolysis reaction can be subjected to acid washing, alkali washing and water washing to remove impurities, in particular to remove excessive impurities such as metal salt.
And cooling the organic phase, crystallizing, and separating out filter cakes or precipitates by adopting methods such as filtration or centrifugation to obtain the crude 4,4' -dihalogenated benzophenone.
One embodiment of the present invention comprises the steps of:
① Adding the catalyst into halogenated aromatic hydrocarbon, controlling the temperature condition, slowly adding oxalyl chloride, and then maintaining the reaction for 4-6 hr at the temperature until the oxalyl chloride is completely reacted. The hydrochloric acid gas generated by the reaction can be used for the next hydrolysis reaction after being absorbed by water.
② After the reaction, adding aqueous hydrochloric acid solution, and keeping stirring for more than half an hour; standing and layering, and removing a water layer; the organic phase is washed by acid, alkali and water to remove excessive metal salt and other impurities.
③ And cooling the organic phase in the step ② to below 0 ℃, crystallizing and filtering to obtain a crude 4,4' -dihalogenated benzophenone product.
④ Recrystallizing the crude 4,4 '-dihalogenated benzophenone obtained in the step ③ by using an organic solvent to obtain the 4,4' -dihalogenated benzophenone.
The invention adopts the method of acylation and hydrolysis to directly synthesize the 4,4' -dihalogenated benzophenone under the condition of not using high-toxicity reagent, the reaction route is simple to operate and environment-friendly, expensive reagent is not needed, the cost is low, the product yield and purity are high, and the invention is safe and practical and is suitable for industrial production.
Drawings
FIG. 1 is an IR spectrum of 4,4' -difluorobenzophenone, the product of example 1.
Detailed Description
The method of the present invention will be further described with reference to examples below to facilitate understanding of the specific technical aspects of the present invention, but the scope of protection of the present invention is not limited to the following examples.
Example 1:
13.3g of AlCl 3 are weighed and added into 58g of fluorobenzene, after stirring and heating to 50 ℃, 6.3g of oxalyl chloride is slowly added dropwise. After the dripping is finished, maintaining the reaction temperature, continuously stirring for 5hr, and absorbing hydrochloric acid tail gas generated in the reaction process by water to obtain hydrochloric acid solution which can be used for hydrolysis. After the reaction, 20mL of 10% hydrochloric acid solution was added for hydrolysis, and the mixture was stirred for half an hour, followed by standing and separation of an organic phase.
The organic phase is washed with acid, alkali and water to remove impurities such as metal salt. The obtained organic phase is cooled to below 0 ℃, crystallized and filtered, and the crude 4,4' -difluorobenzophenone is obtained. After the crude product is recrystallized by solvent, 20.2g of 4,4' -difluorobenzophenone can be obtained, and the yield is 93%. Content (GC): 99.93%, melting point: 107.5-107.9 ℃.
Example 2:
16.4g of ZnCl 2 was weighed into 58g of fluorobenzene, heated to 70℃with stirring and then 6.3g of oxalyl chloride was slowly added dropwise. After the dripping is finished, maintaining the reaction temperature, continuously stirring for 4hr, and absorbing hydrochloric acid tail gas generated in the reaction process by water to obtain hydrochloric acid solution which can be used for hydrolysis. After the reaction, 20mL of 10% hydrochloric acid solution was added for hydrolysis, and the mixture was stirred for half an hour, followed by standing and separation of an organic phase.
The organic phase is washed with acid, alkali and water to remove impurities such as metal salt. The obtained organic phase is cooled to below 0 ℃, crystallized and filtered, and the crude 4,4' -difluorobenzophenone is obtained. After the crude product is recrystallized by solvent, 19.2g of 4,4' -difluorobenzophenone can be obtained, and the yield is 88%. Content (GC): 99.86%, melting point: 107.7-108.0 ℃.
Example 3:
13.3g of AlCl 3 are weighed into 68g of chlorobenzene, heated to 50℃with stirring and 6.3g of oxalyl chloride are slowly added dropwise. After the dripping is finished, maintaining the reaction temperature, continuously stirring for 5hr, and absorbing hydrochloric acid tail gas generated in the reaction process by water to obtain hydrochloric acid solution which can be used for hydrolysis. After the reaction, 20mL of 10% hydrochloric acid solution was added for hydrolysis, and the mixture was stirred for half an hour, followed by standing and separation of an organic phase.
The organic phase is washed with acid, alkali and water to remove impurities such as metal salt. The obtained organic phase is cooled to below 0 ℃, crystallized and filtered, and the crude 4,4' -dichloro benzophenone is obtained. After the crude product is recrystallized by solvent, 21.5g of 4,4' -dichloro benzophenone can be obtained, and the yield is 86%. Content (GC): 99.72%, melting point: 146.5-147.2 ℃. Comparative example 1:
AlCl 3 was replaced by ZnCl 2 in example 1, wherein the amount of ZnCl 2 was 13.6g and the yield was 82%. Comparative example 2:
AlCl 3 was replaced by FeCl 3 in example 1, wherein the amount of FeCl 3 was 16.2g and the yield was 79%.
Comparative example 3:
The fluorobenzene was changed to chlorobenzene in example 2 in an amount of 68g in a yield of 90%.
Claims (6)
1. A method for synthesizing 4,4' -dihalobenzophenone, which is characterized by comprising the following steps: heating and reacting a compound shown in the formula (I) with oxalyl chloride under the action of a catalyst, and absorbing HCl gas generated in the reaction process by water to obtain a hydrochloric acid solution; adding hydrochloric acid after the reaction to react, standing for layering after the reaction, removing a water layer, and cooling and crystallizing the obtained organic phase after washing and removing impurities to obtain a compound 4,4 '-difluorobenzophenone or 4,4' -dichlorobenzophenone shown in the formula (II); the mass fraction of the hydrochloric acid is 5-37%, and the volume-mass ratio of the hydrochloric acid to the oxalyl chloride is 1-5:1 mL/g; the catalyst is AlCl 3、FeCl3 or ZnCl 2;
Wherein X is F or Cl.
2. The process according to claim 1, wherein the reaction temperature of the compound of formula (I) with oxalyl chloride is 40-90 ℃.
3. The process according to claim 2, wherein the reaction temperature of the compound of formula (I) with oxalyl chloride is 50 to 70 ℃.
4. The process according to claim 1, characterized in that the molar ratio of the compound of formula (I) to oxalyl chloride is 10 to 15:1; the mol ratio of the catalyst to the oxalyl chloride is 1-4:1.
5. The process according to claim 4, wherein the molar ratio of the compound of formula (I) to oxalyl chloride is from 11 to 13:1; the molar ratio of the catalyst to the oxalyl chloride is 2-3:1.
6. The method according to claim 1, wherein the hydrolysis reaction is carried out after adding hydrochloric acid, the mass fraction of the hydrochloric acid is 8-25%, and the volume-mass ratio of the hydrochloric acid to oxalyl chloride is 3-4:1mL/g.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202211402276.3A CN115784856B (en) | 2022-11-09 | 2022-11-09 | Method for synthesizing 4,4' -dihalogenated benzophenone |
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| CN202211402276.3A CN115784856B (en) | 2022-11-09 | 2022-11-09 | Method for synthesizing 4,4' -dihalogenated benzophenone |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104211590A (en) * | 2014-09-16 | 2014-12-17 | 浙江先锋科技股份有限公司 | Preparation method of 2, 4-dichloro-fluorobenzoyl chloride |
| CN104447658A (en) * | 2014-12-04 | 2015-03-25 | 杭州杜易科技有限公司 | Method for preparing halogenated 4-chromanone derivative |
| CN106278848A (en) * | 2016-08-16 | 2017-01-04 | 甘肃金盾化工有限责任公司 | A kind of production technology of double [4 (2 hydroxyl 2 methylpropionyl) phenyl] methane |
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- 2022-11-09 CN CN202211402276.3A patent/CN115784856B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104211590A (en) * | 2014-09-16 | 2014-12-17 | 浙江先锋科技股份有限公司 | Preparation method of 2, 4-dichloro-fluorobenzoyl chloride |
| CN104447658A (en) * | 2014-12-04 | 2015-03-25 | 杭州杜易科技有限公司 | Method for preparing halogenated 4-chromanone derivative |
| CN106278848A (en) * | 2016-08-16 | 2017-01-04 | 甘肃金盾化工有限责任公司 | A kind of production technology of double [4 (2 hydroxyl 2 methylpropionyl) phenyl] methane |
Non-Patent Citations (1)
| Title |
|---|
| Unsymmetrical Diaryl Ketones from Arenes;Douglass F. Taber;J. Org. Chem.;第65卷;254 -255 * |
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