CN115650859A - Preparation method of 2,4-difluoroaniline - Google Patents
Preparation method of 2,4-difluoroaniline Download PDFInfo
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- CN115650859A CN115650859A CN202211294203.7A CN202211294203A CN115650859A CN 115650859 A CN115650859 A CN 115650859A CN 202211294203 A CN202211294203 A CN 202211294203A CN 115650859 A CN115650859 A CN 115650859A
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- CN
- China
- Prior art keywords
- difluoroaniline
- difluoronitrobenzene
- reaction
- catalyst
- preparation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- CEPCPXLLFXPZGW-UHFFFAOYSA-N 2,4-difluoroaniline Chemical compound NC1=CC=C(F)C=C1F CEPCPXLLFXPZGW-UHFFFAOYSA-N 0.000 title claims abstract description 29
- 238000002360 preparation method Methods 0.000 title claims abstract description 8
- 238000006243 chemical reaction Methods 0.000 claims abstract description 37
- RJXOVESYJFXCGI-UHFFFAOYSA-N 2,4-difluoro-1-nitrobenzene Chemical compound [O-][N+](=O)C1=CC=C(F)C=C1F RJXOVESYJFXCGI-UHFFFAOYSA-N 0.000 claims abstract description 25
- 238000000034 method Methods 0.000 claims abstract description 23
- 229910000564 Raney nickel Inorganic materials 0.000 claims abstract description 12
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 11
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 11
- 239000001257 hydrogen Substances 0.000 claims abstract description 11
- 239000003054 catalyst Substances 0.000 claims abstract description 6
- 239000002994 raw material Substances 0.000 claims abstract description 6
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 4
- 238000005984 hydrogenation reaction Methods 0.000 claims abstract description 3
- NPXOKRUENSOPAO-UHFFFAOYSA-N Raney nickel Chemical compound [Al].[Ni] NPXOKRUENSOPAO-UHFFFAOYSA-N 0.000 claims description 8
- 239000000203 mixture Substances 0.000 claims description 4
- 238000002156 mixing Methods 0.000 claims description 2
- 239000012535 impurity Substances 0.000 abstract description 4
- 239000002904 solvent Substances 0.000 abstract description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 16
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 12
- 239000000706 filtrate Substances 0.000 description 9
- 229910052757 nitrogen Inorganic materials 0.000 description 8
- 239000012295 chemical reaction liquid Substances 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 4
- 239000003086 colorant Substances 0.000 description 4
- 238000001816 cooling Methods 0.000 description 4
- 238000007599 discharging Methods 0.000 description 4
- 238000001914 filtration Methods 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- 239000007868 Raney catalyst Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 3
- 238000005292 vacuum distillation Methods 0.000 description 3
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 2
- 238000006555 catalytic reaction Methods 0.000 description 2
- 239000003814 drug Substances 0.000 description 2
- 239000012074 organic phase Substances 0.000 description 2
- 239000000575 pesticide Substances 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 2
- KTXFXDMDYZIXSJ-UHFFFAOYSA-N 2,4-difluorobenzamide Chemical compound NC(=O)C1=CC=C(F)C=C1F KTXFXDMDYZIXSJ-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 235000019270 ammonium chloride Nutrition 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000009903 catalytic hydrogenation reaction Methods 0.000 description 1
- 238000006115 defluorination reaction Methods 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 238000006193 diazotization reaction Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- UKVIEHSSVKSQBA-UHFFFAOYSA-N methane;palladium Chemical compound C.[Pd] UKVIEHSSVKSQBA-UHFFFAOYSA-N 0.000 description 1
- 238000006396 nitration reaction Methods 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000006722 reduction reaction Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 239000002351 wastewater Substances 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 relates to a preparation method for preparing 2,4-difluoroaniline by catalyzing 2,4-difluoronitrobenzene and hydrogenating, wherein the method comprises the following steps: the 2,4-difluoroaniline is prepared by taking 2,4-difluoronitrobenzene and hydrogen as raw materials and Raney's nickel as a catalyst through hydrogenation reaction under the solvent-free condition. The preparation method of 2,4-difluoroaniline provided by the invention can greatly reduce the cost of the catalyst while ensuring good conversion rate and yield, does not additionally add other solvents, can effectively control reaction impurities, and improves the reaction efficiency.
Description
Technical Field
The invention relates to a chemical synthesis method, in particular to a preparation method of a pesticide and medicine intermediate 2,4-difluoroaniline.
Background
2,4-difluoroaniline is an important organic synthesis intermediate, and is an important intermediate for medicines and pesticides. At present, m-diphenylamine is obtained by diazotization, displacement, nitration and reduction in the medical industry, and the method has the disadvantages of complex synthetic process and low yield. Patent CN114053959A mentions that 2,4-difluoronitrobenzene is reduced by using Fe powder and ammonium chloride aqueous solution, and the method can generate more iron waste; CN108558674A mentions that 2,4-difluoroaniline is obtained by degrading 2,4-difluorobenzamide, the process is simple, but the raw material price is high and more waste water is generated; in CN108947849A, 2,4-difluoroaniline is produced by a solvent-free catalytic hydrogenation method, expensive palladium carbon is used as a catalyst, and a phosphate auxiliary component is additionally added in the process.
Disclosure of Invention
The invention provides a preparation method of 2,4-difluoroaniline, which comprises the following steps:
the 2,4-difluoroaniline is prepared by taking 2,4-difluoronitrobenzene and hydrogen as raw materials and Raney's nickel as a catalyst through hydrogenation reaction under the solvent-free condition.
The foregoing process further comprises the step of first mixing 2,4-difluoroaniline with a raney nickel catalyst to provide a mixture.
The method also includes the step of first adding the material 2,4-difluoronitrobenzene to the mixture.
The aforementioned addition mode is batch addition or continuous addition. The defluorination impurity can be effectively prevented from being generated by a mode of adding in batches or continuously. The generation of defluorinated impurities can cause the reaction liquid to be yellow or brown, and in order to distinguish the colors, the colors of the reaction liquid are sequenced according to the sequence of increasing numbers 1 to 5 in the specific embodiment of the invention.
The mass ratio of 2,4-difluoronitrobenzene to 2,4-difluoroaniline is 1 to 10 to 1. In some embodiments, the mass ratio of 2,4-difluoronitrobenzene to 2,4-difluoroaniline may be 2 to 1, 3 to 1, 4 to 1, 5 to 1, 6 to 1, 7 to 1, 8 to 1, or 9 to 1.
Further, the mass ratio of 2,4-difluoronitrobenzene to 2,4-difluoroaniline is 2 to 6 to 1.
Further, the mass ratio of 2,4-difluoronitrobenzene to 2,4-difluoroaniline is 4 to 1.
The reaction temperature of the foregoing reaction is 60 ℃ to 100 ℃, preferably 65 ℃ to 90 ℃, more preferably 75 ℃ to 85 ℃, most preferably 80 ℃.
The mass ratio of the Raney nickel catalyst to 2,4-difluoronitrobenzene is 1 to 10 to 100, preferably 3 to 7 to 100, more preferably 5 to 100.
When the raw material 2,4-difluoronitrobenzene is added, 2,4-difluoronitrobenzene is added at a rate that the system does not exceed the maximum temperature required by the reaction. For example, when the reaction temperature is 80 ℃,2,4-difluoronitrobenzene is fed at a rate that controls the system to not exceed 80 ℃.
Specific embodiment in the 2L high-pressure reaction kettle, the adding speed is 2g/min to 30g/min, preferably 3g/min to 15g/min, and more preferably 6g/min to 7g/min. In a specific embodiment, the aforementioned addition time is 0.5h to 5h, preferably 1h to 4h, more preferably 2h.
The aforementioned reaction is carried out under a pressure, and may be carried out under a pressure of 0.8MPa to 3 MPa. In some embodiments, the reaction pressure may be 0.9MPa, 1.0MPa, 1.1MPa, 1.2MPa, 1.5MPa, 2.0MPa, 2.5MPa, or 3.0MPa. In a particular embodiment of the invention, the reaction pressure is 2MPa.
Compared with the prior art, the preparation method of 2,4-difluoroaniline provided by the invention has the following advantages:
(1) The Raney nickel catalyst is adopted, so that the catalyst cost is greatly reduced.
(2) The method adopts a batch adding or continuous adding mode, effectively controls reaction impurities and improves reaction efficiency.
(3) No additional components are required.
(4) No additional solvent is required.
Detailed Description
In the examples, the reaction solution was divided into colors of shades, wherein the colors were gradually deepened in the order of No. 1 to No. 5, and 1-almost colorless; 2-shallower; 3-shallow; 4-deeper; 5-deep.
The examples relate to the following reaction formulae:
example 1
Adding 500g of 2, 4-difluoronitrobenzene, 500g of tetrahydrofuran and 25g of raney nickel into a 2L high-pressure reaction kettle, introducing nitrogen to replace air in the high-pressure reaction kettle, introducing hydrogen after replacement is finished, starting a heating control system, setting the reaction temperature to be 80 ℃, reacting for 360min, and continuously introducing hydrogen to maintain the pressure in the kettle to be 2MPa in the process. And after the reaction is finished, cooling to room temperature. Discharging under the protection of nitrogen, filtering the materials to obtain a reaction solution, and analyzing by LC, wherein the relative content of 2,4-difluoroaniline in the filtrate is 98%.
Distilling the filtrate at 65 deg.C under vacuum degree of-0.09 kPa to remove tetrahydrofuran and water. Then, vacuum distillation was continued at 95 ℃ under a vacuum degree of-0.09 kPa to collect 393.5g of 77-78 ℃ distillate, which was 2,4-difluoroaniline, and the relative content was 99% by LC analysis, with a yield of 97%.
The catalytic reaction conditions were varied and the results obtained are shown in table 1.
TABLE 1
Example 2
Adding 500g2, 4-difluoronitrobenzene, 500g methanol and 25g Raney nickel into a 2L high-pressure reaction kettle, introducing nitrogen to replace air in the high-pressure reaction kettle, introducing hydrogen after replacement is finished, starting a heating control system, setting the reaction temperature at 80 ℃, reacting for 360min, and continuously introducing hydrogen to maintain the pressure in the kettle at 2MPa in the process. And cooling to room temperature after the reaction is finished. Discharging under the protection of nitrogen, filtering the materials to obtain filtrate, and analyzing by LC to obtain the filtrate with the relative content of 2,4-difluoroaniline of 98.5%.
Distilling the filtrate at 65 deg.C under vacuum degree of-0.09 kPa to remove methanol and water. Then, the vacuum distillation is continued at 95 ℃ and under the vacuum degree of-0.09 kPa, 395.7g of fraction at 77-78 ℃ is collected, the fraction is 2,4-difluoroaniline, and the relative content is 99 percent by LC analysis, and the yield is 97.5 percent.
The catalytic reaction conditions were varied and the results obtained are shown in table 2.
TABLE 2
Example 3
500g of methanol and 25g of Raney's nickel are added into a 2L high-pressure reaction kettle, and 500g of 2, 4-difluoronitrobenzene is added into a dropping tank (500 ml). Introducing nitrogen to replace air in the high-pressure reaction kettle, introducing hydrogen after replacement, starting a heating control system, setting the reaction temperature to be 80 ℃, and dropwise adding 2,4-difluoronitrobenzene at the dropwise adding speed of 4.2g/min for 120min. After the dropwise addition, the reaction is carried out for 240min, and hydrogen is continuously introduced in the process to maintain the pressure in the kettle to be 2MPa. And after the reaction is finished, cooling to room temperature. Discharging under the protection of nitrogen, filtering the materials to obtain a reaction solution, observing the color number of the reaction solution to be 3, and analyzing by LC, wherein the relative content of 2,4-difluoroaniline in the filtrate is 99.6%.
Distilling the filtrate at 65 deg.C under vacuum degree of-0.09 kPa to remove methanol and water. Then, vacuum distillation was continued at 95 ℃ under a vacuum degree of-0.09 kPa to collect 401.5g of a fraction at 77-78 ℃ which was 2,4-difluoroaniline, and the relative content was 99.7% by LC analysis, with a yield of 99%.
Example 4
Adding 25g of Raney nickel and 200g2, 4-difluoroaniline into a 2L high-pressure reaction kettle; 800g of 2, 4-difluoronitrobenzene was added to the dropping pot. Introducing nitrogen to replace air in the high-pressure reaction kettle, introducing hydrogen after replacement, starting a heating control system, starting the heating control system, and dripping 2,4-difluoronitrobenzene at the dripping speed of 6.67g/min when the temperature reaches 80 ℃. After the dropwise addition, the reaction is carried out for 240min, and hydrogen is continuously introduced in the process to maintain the pressure in the kettle to be 2MPa. And after the reaction is finished, cooling to room temperature. Discharging under the protection of nitrogen, filtering the materials to obtain filtrate, splitting phases of the filtrate, wherein the upper layer is a water phase, the lower layer is an organic phase, namely reaction liquid, the observed color number of the reaction liquid is 1, and the relative content of 2,4-difluoroaniline of the reaction liquid is 99.5% through LC analysis.
The organic phase was distilled at 65 ℃ under a vacuum of-0.09 kPa to remove water. Then, the distillation was continued under reduced pressure (95 ℃ C., vacuum degree-0.09 kPa), 642.8g of fraction at 77-78 ℃ was collected, 2,4-difluoroaniline was obtained, and the relative content was 99.6% by LC analysis, and the yield was 99%.
Example 5
The acceleration of 2,4-difluoronitrobenzene drops was adjusted as in example 4 and the results are shown in table 3.
TABLE 3
Claims (9)
1. The invention relates to a preparation method of 2,4-difluoroaniline, which is characterized by comprising the following steps: the 2,4-difluoroaniline is prepared by taking 2,4-difluoronitrobenzene and hydrogen as raw materials and Raney's nickel as a catalyst through hydrogenation reaction under the solvent-free condition.
2. The method of claim 1 further comprising the step of first mixing 2,4-difluoroaniline with a raney nickel catalyst to provide a mixture.
3. The method of claim 2 further comprising the step of first adding a feedstock 2,4-difluoronitrobenzene to the mixture.
4. The method according to claim 3, wherein the addition is carried out in a batch manner or a continuous manner.
5. The method of claim 2, wherein the mass ratio of 2,4-difluoronitrobenzene to 2,4-difluoroaniline is 1 to 10 to 1, preferably 2 to 6 to 1, more preferably 4 to 1.
6. The method of claim 1, wherein the reaction is carried out at a temperature of from 60 ℃ to 100 ℃, preferably from 65 ℃ to 90 ℃, more preferably from 75 ℃ to 85 ℃, and most preferably 80 ℃.
7. The method of claim 1, wherein the mass ratio of raney nickel catalyst to 2,4-difluoronitrobenzene is 1 to 10 to 100, preferably 3 to 7 to 100, more preferably 5 to 100.
8. The method of claim 3, wherein the raw material 2,4-difluoronitrobenzene is fed at a rate such that the system does not exceed the maximum temperature required for the reaction 2,4-difluoronitrobenzene is fed.
9. The method of claim 8, wherein the addition time is 0.5 to 5 hours, preferably 1 to 4 hours, more preferably 2 hours.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211294203.7A CN115650859A (en) | 2022-10-21 | 2022-10-21 | Preparation method of 2,4-difluoroaniline |
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| CN202211294203.7A CN115650859A (en) | 2022-10-21 | 2022-10-21 | Preparation method of 2,4-difluoroaniline |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54109928A (en) * | 1977-10-31 | 1979-08-29 | Merck & Co Inc | Manufacture of 2*44difluoroaniline |
| US5689021A (en) * | 1993-10-07 | 1997-11-18 | Rhone-Poulenc Chimie | Raney-type catalysts for the hydrogenation of halonitroaromatic compounds |
| US6156933A (en) * | 1996-04-17 | 2000-12-05 | Degussa-Huls Ag | Supercritical hydrogenation |
| CN108947849A (en) * | 2018-08-17 | 2018-12-07 | 济南和润化工科技有限公司 | A kind of method of solvent-free catalytic hydrogenation production 2,4 difluorobenzene amine |
| CN114621097A (en) * | 2022-03-29 | 2022-06-14 | 浙江解氏新材料股份有限公司 | Method for preparing 2, 4-difluoroaniline through catalytic hydrogenation of 2, 4-difluoronitrobenzene |
-
2022
- 2022-10-21 CN CN202211294203.7A patent/CN115650859A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54109928A (en) * | 1977-10-31 | 1979-08-29 | Merck & Co Inc | Manufacture of 2*44difluoroaniline |
| US5689021A (en) * | 1993-10-07 | 1997-11-18 | Rhone-Poulenc Chimie | Raney-type catalysts for the hydrogenation of halonitroaromatic compounds |
| US6156933A (en) * | 1996-04-17 | 2000-12-05 | Degussa-Huls Ag | Supercritical hydrogenation |
| CN108947849A (en) * | 2018-08-17 | 2018-12-07 | 济南和润化工科技有限公司 | A kind of method of solvent-free catalytic hydrogenation production 2,4 difluorobenzene amine |
| CN114621097A (en) * | 2022-03-29 | 2022-06-14 | 浙江解氏新材料股份有限公司 | Method for preparing 2, 4-difluoroaniline through catalytic hydrogenation of 2, 4-difluoronitrobenzene |
Non-Patent Citations (2)
| Title |
|---|
| P.H.格罗金斯: "《化工有机合成单元过程》", 30 June 1972, 燃料化学工业出版社 , pages: 75 * |
| 胡俊;卢春山;张群峰;刘维;马磊;李小年;: "Mo改性雷尼镍对2, 4-二氟硝基苯液相催化加氢的影响", 化工生产与技术, no. 02, pages 5 * |
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