CN117447343A - Preparation method of pretilachlor - Google Patents
Preparation method of pretilachlor Download PDFInfo
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- CN117447343A CN117447343A CN202311131649.2A CN202311131649A CN117447343A CN 117447343 A CN117447343 A CN 117447343A CN 202311131649 A CN202311131649 A CN 202311131649A CN 117447343 A CN117447343 A CN 117447343A
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- Prior art keywords
- reaction
- pretilachlor
- amine ether
- ether
- amine
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- YLPGTOIOYRQOHV-UHFFFAOYSA-N Pretilachlor Chemical compound CCCOCCN(C(=O)CCl)C1=C(CC)C=CC=C1CC YLPGTOIOYRQOHV-UHFFFAOYSA-N 0.000 title claims abstract description 29
- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims abstract description 138
- 150000001412 amines Chemical class 0.000 claims abstract description 67
- 238000006243 chemical reaction Methods 0.000 claims abstract description 42
- 239000006227 byproduct Substances 0.000 claims abstract description 29
- BHDSGQOSIWVMJW-UHFFFAOYSA-N 1-(2-chloroethoxy)propane Chemical compound CCCOCCCl BHDSGQOSIWVMJW-UHFFFAOYSA-N 0.000 claims abstract description 26
- 238000000034 method Methods 0.000 claims abstract description 26
- FOYHNROGBXVLLX-UHFFFAOYSA-N 2,6-diethylaniline Chemical compound CCC1=CC=CC(CC)=C1N FOYHNROGBXVLLX-UHFFFAOYSA-N 0.000 claims abstract description 20
- 230000015572 biosynthetic process Effects 0.000 claims abstract description 19
- 238000003786 synthesis reaction Methods 0.000 claims abstract description 16
- 239000000654 additive Substances 0.000 claims abstract description 10
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 42
- 239000000543 intermediate Substances 0.000 claims description 28
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 14
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 9
- 238000005406 washing Methods 0.000 claims description 8
- VGCXGMAHQTYDJK-UHFFFAOYSA-N Chloroacetyl chloride Chemical compound ClCC(Cl)=O VGCXGMAHQTYDJK-UHFFFAOYSA-N 0.000 claims description 7
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 7
- 230000010933 acylation Effects 0.000 claims description 6
- 238000005917 acylation reaction Methods 0.000 claims description 6
- 230000035484 reaction time Effects 0.000 claims description 6
- 238000004321 preservation Methods 0.000 claims description 5
- 239000007788 liquid Substances 0.000 claims description 4
- 239000003513 alkali Substances 0.000 claims description 2
- 238000004821 distillation Methods 0.000 claims description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 2
- 238000011534 incubation Methods 0.000 claims 4
- 230000000996 additive effect Effects 0.000 abstract description 5
- 238000000926 separation method Methods 0.000 abstract description 5
- 239000012535 impurity Substances 0.000 abstract description 3
- 239000000126 substance Substances 0.000 description 6
- RCJVRSBWZCNNQT-UHFFFAOYSA-N dichloridooxygen Chemical compound ClOCl RCJVRSBWZCNNQT-UHFFFAOYSA-N 0.000 description 5
- 239000003153 chemical reaction reagent Substances 0.000 description 4
- 239000004009 herbicide Substances 0.000 description 4
- 239000012074 organic phase Substances 0.000 description 4
- 230000002363 herbicidal effect Effects 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- YEYKMVJDLWJFOA-UHFFFAOYSA-N 2-propoxyethanol Chemical compound CCCOCCO YEYKMVJDLWJFOA-UHFFFAOYSA-N 0.000 description 2
- KEAYESYHFKHZAL-UHFFFAOYSA-N Sodium Chemical compound [Na] KEAYESYHFKHZAL-UHFFFAOYSA-N 0.000 description 2
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 2
- 239000012752 auxiliary agent Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 150000003335 secondary amines Chemical class 0.000 description 2
- 239000012312 sodium hydride Substances 0.000 description 2
- 229910000104 sodium hydride Inorganic materials 0.000 description 2
- DTEGEQGTAYAXBC-UHFFFAOYSA-N 2,6-diethyl-n-(2-propoxyethyl)aniline Chemical compound CCCOCCNC1=C(CC)C=CC=C1CC DTEGEQGTAYAXBC-UHFFFAOYSA-N 0.000 description 1
- UENGBOCGGKLVJJ-UHFFFAOYSA-N 2-chloro-1-(2,4-difluorophenyl)ethanone Chemical compound FC1=CC=C(C(=O)CCl)C(F)=C1 UENGBOCGGKLVJJ-UHFFFAOYSA-N 0.000 description 1
- YFPMKTSZVUDZDO-UHFFFAOYSA-N 2-propoxyacetaldehyde Chemical compound CCCOCC=O YFPMKTSZVUDZDO-UHFFFAOYSA-N 0.000 description 1
- -1 2-propoxyethyl Chemical group 0.000 description 1
- 229960001413 acetanilide Drugs 0.000 description 1
- 239000000010 aprotic solvent Substances 0.000 description 1
- VXIVSQZSERGHQP-UHFFFAOYSA-N chloroacetamide Chemical group NC(=O)CCl VXIVSQZSERGHQP-UHFFFAOYSA-N 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- ODZPKZBBUMBTMG-UHFFFAOYSA-N sodium amide Chemical class [NH2-].[Na+] ODZPKZBBUMBTMG-UHFFFAOYSA-N 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- 235000017557 sodium bicarbonate Nutrition 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C231/00—Preparation of carboxylic acid amides
- C07C231/02—Preparation of carboxylic acid amides from carboxylic acids or from esters, anhydrides, or halides thereof by reaction with ammonia or amines
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
- C07C213/04—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton by reaction of ammonia or amines with olefin oxides or halohydrins
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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 preparation method of pretilachlor, which is characterized in that a proper amount of disubstituted amine ether byproducts are added in the reaction of 2, 6-diethyl aniline and chloroethyl propyl ether, so that the generation of the disubstituted amine ether byproducts in the amine ether synthesis process is inhibited, the selectivity and the yield of an amine ether intermediate are obviously improved, and the yield of pretilachlor is further improved. In addition, the disubstituted amine ether byproduct is added in the amine ether synthesis process and used as an additive, and the additive is an inherent impurity in the amine ether synthesis process, so that no new impurity is introduced into a reaction system as the additive, and separation can be realized through a conventional rectification method.
Description
Technical Field
The application belongs to the technical field of herbicides, and particularly relates to a preparation method of pretilachlor.
Background
Pretilachlor is a chloroacetamide herbicide developed by the company just before, and belongs to a herbicide special for paddy fields, and the chemical name of the pretilachlor herbicide is: 2-chloro-2 ',6' -diethyl-N- (2-propoxyethyl) -N-acetanilide with CAS number 51218-49-6.
The prior art is mainly used for preparing pretilachlor by an amine ether method, namely, 2, 6-diethyl aniline is used as a raw material, and is used for preparing key intermediates 2, 6-diethyl-N- (2-propoxyethyl) aniline (commonly known as amine ether) by using ethylene glycol mono-N-propyl ether (CN 102408352A; CN102219654A; liaoning chemical, 2000,29 (2): 112-113), ethylene glycol mono-N-propyl ether sulfonate (CN 102229545A; liaoning chemical, 45 (6): 690-692), chloroethyl propyl ether (US 4324580; zhejiang chemical, 39 (7); 17-18; chemical reagent, 33 (3): 283-285; CN102173998A; CN105272869A; CN104478741A; CN108658791A) or 2-propoxyacetaldehyde (CN 105601529A; journal of Chemical & Pharmaceutical Research,2013,5 (12): 1320-1324) and the like, and then reacting with chloroacetyl chloride under alkaline conditions to synthesize pretilachlor:
in the above synthetic route, the chloroethyl propyl ether route has the advantages of low raw material price, simple equipment, low cost and less three wastes, but has the disadvantage that the di-substituted amine ether byproduct +_ is easy to generate in the reaction process>The yield of the monosubstituted amine ether intermediates is always difficult to increase (Zhejiang chemical 39 (7); 17-18).
To increase the selectivity of the amine ether intermediate and reduce the formation of di-substituted amine ether by-products, wu Jinming et al, nanton university reported that reacting 2, 6-diethylaniline with sodium hydride in an aprotic solvent to form an amino sodium salt followed by reaction with chloroethyl propyl ether could give the amine ether intermediate in 90% yield (chemical reagent, 33 (3): 283-285; NC 102173998A), but the process was not suitable for commercial production due to the instability of sodium hydride. In addition, du Xiaohua of the university of Zhejiang industry reports that by adding a novel auxiliary agent (N, N-di-N-propyl-2-propoxyethylamine) in the reaction process of 2, 6-diethylaniline and chloroethyl propyl ether, the fluidity of the reaction system can be improved, the selectivity and the yield of the target product can be respectively up to 96.0% and 89.2% (CN 111100019A; the research on the clean production of pretilachlor, the university of Zhejiang industry, shuoshi, du Jiawei), however, the method needs to use a specific novel auxiliary agent, the separation difficulty of the product is increased, and the selectivity improvement on the amine ether intermediate is not obvious. Through intensive researches, the invention discovers that the selectivity and the yield of the amine ether intermediate can be remarkably improved by adding a proper amount of disubstituted amine ether byproducts in the reaction of 2, 6-diethylaniline and chloroethyl propyl ether, and the invention is further completed.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a preparation method of pretilachlor. The method can remarkably improve the selectivity and yield of the amine ether intermediate by adding a proper amount of disubstituted amine ether byproducts in the reaction of the 2, 6-diethylaniline and the chloroethyl propyl ether, and can not cause the increase of the separation difficulty of the product because no other reagent is introduced.
The preparation method of pretilachlor provided by the invention comprises the following steps:
(1) Amine ether synthesis procedure
Adding 2, 6-diethyl aniline (DEA), chloroethyl propyl ether (chloroether), sodium hydroxide solution and a certain amount of disubstituted amine ether byproducts serving as additives into an amine ether synthesis kettle for reaction, and after the reaction is completed, sequentially obtaining excessive 2, 6-diethyl aniline, amine ether intermediates and disubstituted amine ether byproducts through alkali washing and rectification; the reaction formula is as follows:
wherein, the structural formula of the di-substituted amine ether by-product is as follows:
(2) Acylation procedure
Adding the amine ether intermediate prepared in the step (1), toluene and sodium carbonate into an acylation kettle, controlling the temperature to be less than or equal to 50 ℃, dropwise adding chloroacetyl chloride, and carrying out heat preservation reaction to obtain pretilachlor; the reaction formula is as follows:
the process according to the invention as described above, wherein the molar ratio of 2, 6-Diethylaniline (DEA) to chloroethyl propyl ether (chloroether) is from 1:1 to 4:1, preferably from 2 to 3:1.
in the step (1), the concentration of the sodium hydroxide solution is 10-50 wt%, preferably 40-50 wt%, and the feeding mole ratio of sodium hydroxide to chloroethyl propyl ether (chloroether) is 0.5-2:1, preferably 1:1.
in the step (1), the feeding mole ratio of the disubstituted by-product to the chloroethyl propyl ether (chloroether) is 0.05-0.2:1, preferably 0.1:1.
in step (1), the reaction temperature is 120-200 ℃, preferably 160-180 ℃, more preferably 170 ℃; the reaction time is 4 to 24 hours, preferably 8 to 12 hours, more preferably 8 to 10 hours.
In step (1), the alkaline washing uses sodium carbonate solution, sodium hydroxide solution and/or sodium bicarbonate solution; preferably sodium hydroxide solution.
According to the preparation method disclosed by the invention, in the step (2), the temperature is controlled to be less than or equal to 20 ℃, preferably less than or equal to 10 ℃, and the feeding mole ratio of the amine ether intermediate to the chloroacetyl chloride is 1:1-2, preferably 1:1.1-1.5; the feeding mole ratio of the amine ether intermediate to the sodium carbonate is 1:1-2, preferably 1:1.1-1.5. The reaction temperature of the heat preservation reaction is 30-50 ℃, preferably 40-50 ℃, and the reaction time of the heat preservation reaction is 0.5-2h, preferably 1h.
In the step (2), after the reaction is completed, washing and separating liquid are carried out, and distillation under reduced pressure is carried out to collect fractions of 100-105 ℃ and 0.0099MPa, thus obtaining pretilachlor.
Compared with the prior art, the preparation method provided by the invention has the following advantages:
the invention suppresses the generation of the disubstituted amine ether by-product in the amine ether synthesis process by adding a proper amount of the disubstituted amine ether by-product in the reaction of the 2, 6-diethylaniline and the chloroethyl propyl ether, and remarkably improves the selectivity and the yield of the amine ether intermediate, thereby improving the yield of pretilachlor. In addition, the disubstituted amine ether byproduct is added in the amine ether synthesis process and used as an additive, and the disubstituted amine ether byproduct is an inherent byproduct in the amine ether synthesis process, so that no new impurity is introduced into a reaction system as the additive, and separation can be realized through a conventional rectification method.
Detailed Description
The present invention will be described in further detail with reference to specific examples. In the following, unless otherwise indicated, all methods used are within the ordinary skill in the art and all reagents and/or starting materials used are commercially available as usual.
EXAMPLE 1 Synthesis of amine Ether intermediate
2, 6-diethylaniline (149 g,1 mol), chloroethyl propyl ether (40.67 g,0.33 mol), 40wt% sodium hydroxide solution (0.33 mol) and a di-substituted amine ether by-product (10.7 g,0.033 mol) are added as additives to an amine ether synthesis kettle, stirred at 170 ℃ for reaction for 10 hours, after the reaction is completed, the mixture is subjected to alkaline washing by a 32% NaOH solution and separated, and the organic phase is subjected to rectification to obtain excessive 2, 6-diethylaniline (-0.099 MPa, 170 ℃), an amine ether intermediate (-0.099 MPa, 200 ℃) and a di-substituted amine ether by-product in sequence. Wherein the amine ether intermediate was 75.8g, the content was 96.5%, and the yield (based on chloroethyl propyl ether) was 93.3%.
EXAMPLE 2 Synthesis of amine Ether intermediate
2, 6-diethylaniline (149 g,1 mol), chloroethyl propyl ether (61 g,0.5 mol), 40wt% sodium hydroxide solution (0.5 mol) and a di-substituted amine ether by-product (16 g,0.05 mol) were added as additives to an amine ether synthesis vessel, reacted at 180℃for 8 hours with stirring, after the reaction was completed, alkali-washed with a 32% NaOH solution, separated, and the organic phase was distilled to obtain an excess of 2, 6-diethylaniline (-0.099 MPa, 170 ℃) in this order, an amine ether intermediate (-0.099 MPa, 200 ℃) and a di-substituted amine ether by-product. Wherein the amine ether intermediate 111.4g, content 97.1%, yield (based on chloroethyl propyl ether) was 92.0%.
EXAMPLE 3 Synthesis of amine Ether intermediate
2, 6-diethylaniline (149 g,1 mol), chloroethyl propyl ether (61 g,0.5 mol), 40wt% sodium hydroxide solution (0.5 mol) and a secondary amine ether byproduct (12.85 g,0.04 mol) are added as additives into an amine ether synthesis kettle, stirred at 170 ℃ for reaction for 10 hours, after the reaction is completed, the mixture is subjected to alkaline washing by 32% NaOH solution and liquid separation, and the organic phase is subjected to rectification to obtain excessive 2, 6-diethylaniline (-0.099 MPa, 170 ℃), an amine ether intermediate (-0.099 MPa, 200 ℃) and the secondary amine ether byproduct in sequence. Wherein the amine ether intermediate 113.1g, 96.8% content, yield (based on chloroethyl propyl ether) was 93.1%.
Comparative example 1
The procedure of example 1 is followed except that no di-substituted amine ether byproduct is added.
The chloroethyl propyl ether (chloroether) (amine ether formation) conversion was 88.2%, the side reaction (di-substitution by-product formation) conversion was 9.0%, and the amine ether molar yield was 78.5%.
EXAMPLE 4 acylation procedure
Amine ether intermediate (121.8 g,0.5 mol), toluene (200 mL) and sodium carbonate (79.5 g,0.75 mol) are added into an acylation kettle, the temperature is controlled to be less than or equal to 10 ℃, chloroacetyl chloride (70 g,0.625 mol) is added dropwise within 30 minutes, the temperature is slowly raised to 40 ℃ after the dropwise addition, the reaction is carried out for 1 hour under the condition of heat preservation, 200mL of water is added for washing (3 times), the liquid is separated, the organic phase is distilled under reduced pressure to collect the fraction (-0.0099 MPa, 100-105 ℃) to obtain 153.3g of pretilachlor, the content of which is 96.3 percent, and the yield is 94.9 percent.
Claims (10)
1. The preparation method of pretilachlor is characterized by comprising the following steps:
(1) Amine ether synthesis procedure
Adding 2, 6-diethylaniline, chloroethyl propyl ether, sodium hydroxide solution and a certain amount of disubstituted amine ether byproducts serving as additives into an amine ether synthesis kettle for reaction, and after the reaction is completed, sequentially obtaining excessive 2, 6-diethylaniline, amine ether intermediates and disubstituted amine ether byproducts through alkali washing and rectification; the reaction formula is as follows:
wherein, the structural formula of the di-substituted amine ether by-product is as follows:
(2) Acylation procedure
Adding the amine ether intermediate prepared in the step (1), toluene and sodium carbonate into an acylation kettle, controlling the temperature to be less than or equal to 50 ℃, dropwise adding chloroacetyl chloride, and carrying out heat preservation reaction to obtain pretilachlor; the reaction formula is as follows:
2. the preparation method of pretilachlor according to claim 1, wherein the feeding molar ratio of 2, 6-diethylaniline to chloroethyl propyl ether is 1:1-4:1; the feeding mole ratio of the sodium hydroxide to the chloroethyl propyl ether is 0.5-2:1, a step of; the feeding mole ratio of the disubstituted by-product to the chloroethyl propyl ether is 0.05-0.2:1.
3. the preparation method of pretilachlor according to claim 2, wherein the feeding mole ratio of 2, 6-diethylaniline to chloroethyl propyl ether is 2-3:1, a step of; the feeding mole ratio of sodium hydroxide to chloroethyl propyl ether is 1:1, a step of; the molar ratio of the di-substituted by-product to the chloroethyl propyl ether was 0.1:1.
4. the method for preparing pretilachlor according to claim 1, wherein in the step (1), the reaction temperature is 120-200 ℃; the reaction time is 4-24h.
5. The method for preparing pretilachlor according to claim 4, wherein in the step (1), the reaction temperature is 160-180 ℃; the reaction time is 8-12h.
6. The preparation method of pretilachlor according to claim 1, wherein in the step (2), the temperature is controlled to be less than or equal to 20 ℃, and the feeding mole ratio of the amine ether intermediate to the chloroacetyl chloride is 1:1-2; the feeding mole ratio of the amine ether intermediate to the sodium carbonate is 1:1-2.
7. The method for preparing pretilachlor according to claim 6, wherein in the step (2), the temperature is controlled to be less than or equal to 10 ℃, and the feeding mole ratio of the amine ether intermediate to the chloroacetyl chloride is 1:1.1-1.5; the feeding mole ratio of the amine ether intermediate to the sodium carbonate is 1:1.1-1.5.
8. The method for preparing pretilachlor according to claim 1, wherein in the step (2), the reaction temperature of the incubation reaction is 30-50 ℃, and the reaction time of the incubation reaction is 0.5-2h.
9. The method for preparing pretilachlor according to claim 8, wherein in the step (2), the reaction temperature of the incubation reaction is 40-50 ℃, and the reaction time of the incubation reaction is 1h.
10. The method for preparing pretilachlor according to claim 1, wherein in the step (2), after the reaction is completed, washing with water to separate liquid, and collecting 100-105 ℃/-0.0099MPa fraction by reduced pressure distillation to obtain pretilachlor.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202311131649.2A CN117447343A (en) | 2023-09-04 | 2023-09-04 | Preparation method of pretilachlor |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202311131649.2A CN117447343A (en) | 2023-09-04 | 2023-09-04 | Preparation method of pretilachlor |
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