CN115141101A - Synthesis method of 2, 6-difluoroaniline - Google Patents
Synthesis method of 2, 6-difluoroaniline Download PDFInfo
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- CN115141101A CN115141101A CN202210676047.4A CN202210676047A CN115141101A CN 115141101 A CN115141101 A CN 115141101A CN 202210676047 A CN202210676047 A CN 202210676047A CN 115141101 A CN115141101 A CN 115141101A
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- difluoroaniline
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- ODUZJBKKYBQIBX-UHFFFAOYSA-N 2,6-difluoroaniline Chemical compound NC1=C(F)C=CC=C1F ODUZJBKKYBQIBX-UHFFFAOYSA-N 0.000 title claims abstract description 27
- 238000001308 synthesis method Methods 0.000 title description 3
- 239000002904 solvent Substances 0.000 claims abstract description 27
- 238000000034 method Methods 0.000 claims abstract description 23
- 238000006243 chemical reaction Methods 0.000 claims abstract description 16
- AVRQBXVUUXHRMY-UHFFFAOYSA-N 2,6-difluorobenzamide Chemical compound NC(=O)C1=C(F)C=CC=C1F AVRQBXVUUXHRMY-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000003513 alkali Substances 0.000 claims abstract description 11
- YRIZYWQGELRKNT-UHFFFAOYSA-N 1,3,5-trichloro-1,3,5-triazinane-2,4,6-trione Chemical compound ClN1C(=O)N(Cl)C(=O)N(Cl)C1=O YRIZYWQGELRKNT-UHFFFAOYSA-N 0.000 claims abstract description 9
- 229950009390 symclosene Drugs 0.000 claims abstract description 9
- 230000002194 synthesizing effect Effects 0.000 claims abstract description 8
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 19
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 15
- 239000000243 solution Substances 0.000 claims description 9
- 239000007864 aqueous solution Substances 0.000 claims description 8
- 230000015572 biosynthetic process Effects 0.000 claims description 8
- 239000012044 organic layer Substances 0.000 claims description 8
- 238000003786 synthesis reaction Methods 0.000 claims description 8
- 238000000605 extraction Methods 0.000 claims description 5
- 239000000706 filtrate Substances 0.000 claims description 5
- 150000008282 halocarbons Chemical group 0.000 claims description 4
- 238000000967 suction filtration Methods 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims description 2
- 238000001035 drying Methods 0.000 claims description 2
- 230000035484 reaction time Effects 0.000 claims 2
- 125000003158 alcohol group Chemical group 0.000 claims 1
- 239000005708 Sodium hypochlorite Substances 0.000 abstract description 4
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 abstract description 4
- 238000011010 flushing procedure Methods 0.000 abstract description 3
- 239000002351 wastewater Substances 0.000 abstract description 3
- 238000009776 industrial production Methods 0.000 abstract description 2
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 description 12
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 9
- 239000000047 product Substances 0.000 description 7
- 239000000543 intermediate Substances 0.000 description 5
- 241000196324 Embryophyta Species 0.000 description 3
- 239000000575 pesticide Substances 0.000 description 3
- 239000011541 reaction mixture Substances 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 239000005529 Florasulam Substances 0.000 description 2
- QZXATCCPQKOEIH-UHFFFAOYSA-N Florasulam Chemical compound N=1N2C(OC)=NC=C(F)C2=NC=1S(=O)(=O)NC1=C(F)C=CC=C1F QZXATCCPQKOEIH-UHFFFAOYSA-N 0.000 description 2
- RXCPQSJAVKGONC-UHFFFAOYSA-N Flumetsulam Chemical compound N1=C2N=C(C)C=CN2N=C1S(=O)(=O)NC1=C(F)C=CC=C1F RXCPQSJAVKGONC-UHFFFAOYSA-N 0.000 description 2
- 241000205407 Polygonum Species 0.000 description 2
- 235000021307 Triticum Nutrition 0.000 description 2
- 244000098338 Triticum aestivum Species 0.000 description 2
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 244000237956 Amaranthus retroflexus Species 0.000 description 1
- 235000013479 Amaranthus retroflexus Nutrition 0.000 description 1
- 241000208838 Asteraceae Species 0.000 description 1
- 235000011305 Capsella bursa pastoris Nutrition 0.000 description 1
- 240000008867 Capsella bursa-pastoris Species 0.000 description 1
- 240000003173 Drymaria cordata Species 0.000 description 1
- 240000005702 Galium aparine Species 0.000 description 1
- 235000014820 Galium aparine Nutrition 0.000 description 1
- 244000068988 Glycine max Species 0.000 description 1
- 235000010469 Glycine max Nutrition 0.000 description 1
- 240000005979 Hordeum vulgare Species 0.000 description 1
- 235000007340 Hordeum vulgare Nutrition 0.000 description 1
- 240000004658 Medicago sativa Species 0.000 description 1
- 235000017587 Medicago sativa ssp. sativa Nutrition 0.000 description 1
- 235000003990 Monochoria hastata Nutrition 0.000 description 1
- 240000000178 Monochoria vaginalis Species 0.000 description 1
- 240000004274 Sarcandra glabra Species 0.000 description 1
- 235000010842 Sarcandra glabra Nutrition 0.000 description 1
- 235000002594 Solanum nigrum Nutrition 0.000 description 1
- 240000002307 Solanum ptychanthum Species 0.000 description 1
- 241000219793 Trifolium Species 0.000 description 1
- 235000005545 Veronica americana Nutrition 0.000 description 1
- 240000005592 Veronica officinalis Species 0.000 description 1
- 241001251949 Xanthium sibiricum Species 0.000 description 1
- 240000008042 Zea mays Species 0.000 description 1
- 235000005824 Zea mays ssp. parviglumis Nutrition 0.000 description 1
- 235000002017 Zea mays subsp mays Nutrition 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 235000005822 corn Nutrition 0.000 description 1
- 239000012043 crude product Substances 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- JBTWLSYIZRCDFO-UHFFFAOYSA-N ethyl methyl carbonate Chemical compound CCOC(=O)OC JBTWLSYIZRCDFO-UHFFFAOYSA-N 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000001256 steam distillation Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C239/00—Compounds containing nitrogen-to-halogen bonds; Hydroxylamino compounds or ethers or esters thereof
- C07C239/02—Compounds containing nitrogen-to-halogen bonds
- C07C239/06—N-halogenated carboxamides
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/54—Preparation of compounds containing amino groups bound to a carbon skeleton by rearrangement reactions
- C07C209/58—Preparation of compounds containing amino groups bound to a carbon skeleton by rearrangement reactions from or via amides
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a method for synthesizing 2, 6-difluoroaniline, which comprises the following steps: (1) carrying out a first reaction on 2, 6-difluorobenzamide and trichloroisocyanuric acid in a first solvent at a first temperature, and then carrying out first post-treatment to obtain an intermediate; (2) and (2) carrying out a second reaction on the intermediate obtained in the step (1) in an alkali solution at a second temperature, and then carrying out second post-treatment to obtain the 2, 6-difluoroaniline. The method can separate the intermediate chlorinated product in advance, thereby avoiding the danger of flushing, having higher safety, and the trichloroisocyanuric acid is stable and easy to measure, and has simpler and more convenient operation compared with a sodium hypochlorite method. The method can obtain the 2, 6-difluoroaniline with higher purity without rectification, not only greatly simplifies the post-treatment, but also generates less waste water, is more environment-friendly and is suitable for industrial production.
Description
Technical Field
The invention belongs to the technical field of synthesis of pesticide intermediates, and particularly relates to a synthesis method of 2, 6-difluoroaniline.
Background
2, 6-difluoroaniline is an important pesticide intermediate and can be used for preparing pesticides such as florasulam, flumetsulam and the like. The florasulam is mainly used for preventing and killing broadleaf weeds in winter wheat fields, such as cleavers, chickweeds, polygonum weeds, compositae weeds and the like. Flumetsulam is mainly used for preventing and controlling annual and perennial broadleaf weeds in fields such as corn, soybean, wheat, barley, clover, alfalfa and the like, such as shepherd's purse, chloranthus glaber, monochoria indica, polygonum, speedwell, xanthium sibiricum, black nightshade, amaranthus retroflexus, stramonium and the like, and has a certain inhibiting effect on young gramineous weeds.
At present, 2,6-difluorobenzamide is synthesized by a method of using 2,6-difluorobenzamide as a starting material, firstly performing a degradation reaction with sodium hypochlorite in an aqueous solution of sodium hydroxide, then performing steam distillation to obtain a crude product, and finally performing rectification to obtain a pure product [ see chinese patent documents CN102351713A, CN111777515A, CN112457198A, CN113501762 762A, and CN113929583A ], wherein the reaction formula is as follows:
the method has the following disadvantages: (1) sodium hypochlorite is difficult to accurately measure and is complex to operate; (2) the material flushing danger exists, and the safety is low; (3) A large amount of high-salinity wastewater can be generated, and the environmental pollution is serious; (4) Although the purity is high, distillation by steam and rectification are required, resulting in complicated post-treatment.
Disclosure of Invention
The invention aims to solve the problems and provides a method for synthesizing 2, 6-difluoroaniline, which is simple and convenient to operate, high in safety, more environment-friendly and simple in post-treatment.
The technical scheme for realizing the purpose of the invention is as follows: a method for synthesizing 2, 6-difluoroaniline comprises the following steps:
(1) 2, 6-difluorobenzamide and trichloroisocyanuric acid are subjected to a first reaction in a first solvent at a first temperature, and then subjected to a first post-treatment to obtain an intermediate.
(2) And (2) carrying out a second reaction on the intermediate obtained in the step (1) in an alkali solution at a second temperature, and then carrying out second post-treatment to obtain the 2, 6-difluoroaniline.
The reaction formula is as follows:
in the step (1), the molar ratio of the 2, 6-difluorobenzamide to the trichloroisocyanuric acid is 1: 0.3-1: 0.4.
In the step (1), the first solvent is one of an alcohol solvent, an aromatic hydrocarbon solvent, a halogenated hydrocarbon solvent and an ester solvent, preferably an alcohol solvent, and more preferably methanol.
In the step (1), the first temperature is 10 to 40 ℃, preferably 25 ℃.
In the step (1), the time of the first reaction is 0.5 to 3 hours, preferably 1 hour.
In the step (1), the first post-treatment is suction filtration, and the filtrate is dried after the solvent is removed.
The drying temperature is 20-50 ℃, preferably 35 ℃.
In the step (2), the concentration of the alkali solution is 10wt% to 50wt%, preferably 30wt%.
In the step (2), the alkali solution is an aqueous solution of sodium hydroxide or an aqueous solution of potassium hydroxide, preferably an aqueous solution of potassium hydroxide.
In the step (2), the molar ratio of the alkali in the alkali solution to the 2, 6-difluorobenzamide in the step (1) is 2: 1-5: 1, and preferably 3: 1.
In the step (2), the second temperature is 50 to 100 ℃, preferably 90 ℃.
In the step (2), the time of the second reaction is 2 to 6 hours, preferably 3 hours.
In the step (2), the second post-treatment is cooling to room temperature (15-25 ℃), adding a second solvent for extraction, and removing the solvent from the extracted organic layer.
The second solvent is a halogenated hydrocarbon solvent or an aromatic hydrocarbon solvent, preferably a halogenated hydrocarbon solvent, and more preferably dichloromethane.
The invention has the following positive effects:
(1) The method can separate the intermediate chlorinated product in advance, thereby avoiding the danger of flushing, having higher safety, and the trichloroisocyanuric acid is stable and easy to measure, and has simpler and more convenient operation compared with a sodium hypochlorite method.
(2) The method can obtain the 2, 6-difluoroaniline with higher purity without rectification, greatly simplifies post-treatment, generates less waste water, is more environment-friendly, and is suitable for industrial production.
Detailed Description
(example 1)
The method for synthesizing 2, 6-difluoroaniline of this example has the following steps:
(1) a500 mL four-necked flask was charged with 78.5g (0.5 mol) of 2, 6-difluorobenzamide and 300mL of methanol, and after dissolving the mixture with stirring, 38.8g (0.167 mol) of trichloroisocyanuric acid was added to form a white solid, which was then reacted at 25 ℃ for 1 hour with heat.
After the reaction, suction filtration is carried out, and after the solvent is removed from the filtrate under reduced pressure, the filtrate is dried at 35 ℃ to obtain 95.7g of chlorinated product.
(2) A1000 mL four-necked flask was charged with 280.5g (1.5 mol of potassium hydroxide) of a 30wt% aqueous potassium hydroxide solution and 95.7g of the chlorinated product obtained in step (1), stirred to dissolve, and then reacted at 90 ℃ for 3 hours.
After the reaction was completed, the reaction mixture was cooled to 20 ℃ and 250mL of methylene chloride was added for extraction to separate a lower organic layer, and after the solvent was removed from the organic layer, 61.8g of 2, 6-difluoroaniline was obtained in a yield of 95.8% and a GC content of 99.5%.
(example 2)
The method for synthesizing 2, 6-difluoroaniline of this example has the following steps:
(1) a1000 mL four-necked flask was charged with 157.0g (1.0 mol) of 2,6-difluorobenzamide and 600mL of methanol, and after dissolving the compounds with stirring, 79.0g (0.34 mol) of trichloroisocyanuric acid was added thereto to form a white solid, which was then reacted at 25 ℃ for 1 hour.
After the reaction, the reaction solution was filtered, and the filtrate was dried at 35 ℃ after removing the solvent under reduced pressure to obtain 191.0g of chlorinated product.
(2) 561.0g (3.0 mol of potassium hydroxide) of a 30wt% potassium hydroxide aqueous solution and 191.0g of the chlorinated product obtained in step (1) were put into a 1500mL four-necked flask, stirred and dissolved, and then reacted at 90 ℃ for 3 hours.
After the reaction, the reaction mixture was cooled to 20 ℃ and 500ml of methylene chloride was added to conduct extraction, thereby separating a lower organic layer, and after the solvent was removed from the organic layer, 124.1g of 2, 6-difluoroaniline was obtained in a yield of 96.2% and a GC content of 99.7%.
(example 3)
The method for synthesizing 2, 6-difluoroaniline of this example has the following steps:
(1) the same as in example 1.
(2) A1000 mL four-necked flask was charged with 200.0g (1.5 mol of sodium hydroxide) of a 30wt% aqueous solution of sodium hydroxide and 95.7g of the chlorinated product obtained in step (1), stirred to dissolve the components, and then reacted at 90 ℃ for 3 hours.
After the reaction, the reaction mixture was cooled to 20 ℃ and 250mL of dichloromethane was added for extraction to separate the lower organic layer, and after the solvent was removed from the organic layer, 60.5g of 2, 6-difluoroaniline was obtained in a yield of 93.8% and a GC content of 99.4%.
Claims (9)
1. A method for synthesizing 2, 6-difluoroaniline is characterized by comprising the following steps:
(1) carrying out a first reaction on 2, 6-difluorobenzamide and trichloroisocyanuric acid in a first solvent at a first temperature, and then carrying out a first post-treatment to obtain an intermediate;
(2) and (2) carrying out a second reaction on the intermediate obtained in the step (1) in an alkali solution at a second temperature, and then carrying out second post-treatment to obtain the 2, 6-difluoroaniline.
2. The process for the synthesis of 2, 6-difluoroaniline of claim 1, wherein: in the step (1), the molar ratio of the 2, 6-difluorobenzamide to the trichloroisocyanuric acid is 1: 0.3-1: 0.4.
3. The process for the synthesis of 2, 6-difluoroaniline of claim 1, wherein: in the step (1), the first solvent is an alcohol solvent.
4. The process for the synthesis of 2, 6-difluoroaniline of claim 1, wherein: in the step (1), the first temperature is 10-40 ℃, and the first reaction time is 0.5-3 h.
5. The process for the synthesis of 2, 6-difluoroaniline according to claim 1, wherein: in the step (1), the first post-treatment is suction filtration, and the filtrate is dried after the solvent is removed; the drying temperature is 20-50 ℃.
6. The process for the synthesis of 2, 6-difluoroaniline of claim 1, wherein: in the step (2), the concentration of the alkali solution is 10wt% -50 wt%, the alkali solution is sodium hydroxide aqueous solution or potassium hydroxide aqueous solution, and the molar ratio of the alkali in the alkali solution to the 2, 6-difluorobenzamide in the step (1) is 2: 1-5: 1.
7. The process for the synthesis of 2, 6-difluoroaniline of claim 1, wherein: in the step (2), the second temperature is 50-100 ℃, and the second reaction time is 2-6 h.
8. The process for the synthesis of 2, 6-difluoroaniline of claim 1, wherein: in the step (2), the second post-treatment is cooling to room temperature, adding a second solvent for extraction, and removing the solvent from the extracted organic layer.
9. The method of synthesizing 2, 6-difluoroaniline of claim 8, wherein: the second solvent is a halogenated hydrocarbon solvent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210676047.4A CN115141101A (en) | 2022-06-15 | 2022-06-15 | Synthesis method of 2, 6-difluoroaniline |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210676047.4A CN115141101A (en) | 2022-06-15 | 2022-06-15 | Synthesis method of 2, 6-difluoroaniline |
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| CN115141101A true CN115141101A (en) | 2022-10-04 |
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| CN202210676047.4A Pending CN115141101A (en) | 2022-06-15 | 2022-06-15 | Synthesis method of 2, 6-difluoroaniline |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5410082A (en) * | 1993-05-11 | 1995-04-25 | Pfirmann; Ralf | Process for preparing amines |
| CN102351713A (en) * | 2011-08-11 | 2012-02-15 | 扬州天辰精细化工有限公司 | Industrialized production method of 2,6-difluoroaniline |
| CN102993026A (en) * | 2012-11-28 | 2013-03-27 | 张家港市大伟助剂有限公司 | Preparation method of p-phenylenediamine |
| CN109456224A (en) * | 2018-12-17 | 2019-03-12 | 鲁东大学 | A method of preparing 2,6- difluoro indophenols acetic acid esters |
| CN111777515A (en) * | 2020-07-27 | 2020-10-16 | 恒劲生物技术(大连)有限公司 | Safe and green production method of high-quality 2, 6-difluoroaniline |
-
2022
- 2022-06-15 CN CN202210676047.4A patent/CN115141101A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5410082A (en) * | 1993-05-11 | 1995-04-25 | Pfirmann; Ralf | Process for preparing amines |
| CN102351713A (en) * | 2011-08-11 | 2012-02-15 | 扬州天辰精细化工有限公司 | Industrialized production method of 2,6-difluoroaniline |
| CN102993026A (en) * | 2012-11-28 | 2013-03-27 | 张家港市大伟助剂有限公司 | Preparation method of p-phenylenediamine |
| CN109456224A (en) * | 2018-12-17 | 2019-03-12 | 鲁东大学 | A method of preparing 2,6- difluoro indophenols acetic acid esters |
| CN111777515A (en) * | 2020-07-27 | 2020-10-16 | 恒劲生物技术(大连)有限公司 | Safe and green production method of high-quality 2, 6-difluoroaniline |
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