94-80-4Relevant academic research and scientific papers
Synthesis method of substituted phenoxyacetate compound
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Paragraph 0062; 0063; 0064, (2019/08/01)
The invention discloses a synthesis method of a substituted phenoxyacetate compound, relates to a synthesis method of a compound and aims to solve the problems that during current preparation of the substituted phenoxyacetate compound by a condensation method, a large amount of organic agent is consumed, substituted phenol is unlikely to react completely, the content of free phenol in three wastesis high and a very high environmental risk exists. According to the synthesis method, after the substituted phenol is mixed with haloacetate, a condensation reaction is performed in a potassium fluoride system condensing agent under the synergistic catalysis of a phase transfer catalyst and a halogenated hydrocarbon activator to obtain a substituted phenoxyacetic acid compound. The synthesis method is applied to the field of compound synthesis.
Preparation method of 2,4-dichlorophenoxyacetic ester
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, (2019/01/08)
The invention provides a preparation method of 2,4-dichlorophenoxyacetic ester, wherein the preparation method includes the following steps: S1) carrying out a reaction of phenol and methyl chloroacetate under alkaline conditions to obtain methyl phenoxyacetate; S2) carrying out selective chlorination reaction of methyl phenoxyacetate with a chlorinating agent under the action of a catalyst A anda catalyst B to obtain 2,4-methyl dichlorophenoxyacetate, wherein the catalyst A is Lewis acid, and the catalyst B is C5-22 thioethers, thiazoles, isothiazoles and thiophenes or halogenated derivatives thereof; and S3) carrying out transesterification reaction of 2,4-methyl dichlorophenoxyacetate and alcohol under the action of a catalyst, to obtain 2,4-dichlorophenoxyacetic ester, wherein the alcohol is C2-20 alcohol. The selective chlorination reaction is carried out with methyl phenoxyacetate as a raw material, the selectivity of the reaction is improved, the loss of effective components isavoided, the yield of the effective components is greatly improved, and the three-waste treatment capacity, the three-waste treatment difficulty and the treatment cost are reduced.
A phenoxy carboxylic acid ester herbicide preparation method (by machine translation)
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, (2019/01/08)
The invention provides a phenoxy carboxylic acid ester herbicide preparation method, including: S1, phenol in the presence of alkaline substance with the chlorinated carboxylic acid ester condensation reaction, phenoxy carboxylic acid ester obtained; the ClR states the chloro- carboxylic acid ester of the general formula1 COOR, R1 Is C1 - 3 alkylene or alkylidene, R is C1 - 10 alkyl or C3 - 10 cycloalkyl; S2, the [...] ester in the 1st and 2nd catalyst the presence of a catalyst, with the chlorinating agent to carry out the selective chlorination of, get [...] ester; the Lewis acid catalyst is selected from the 1st, the 2nd catalyst is C5 - 22 of the thioether, thiazole, thiophene compounds or different benzisothiazoles; S3, will the [...] ester with an alcohol reaction, as shown in formula I phenoxy carboxylic acid ester herbicide; R3 Is H, Cl or CH3 , R ' is a C4 - 20 alkyl or cycloalkyl. This invention can improve the product quality and the production environment, three waste low. (by machine translation)
Preparation method of 2,4-dichlorophenoxyacetic acid and salt thereof
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Paragraph 0091; 0093, (2019/01/06)
The invention provides a preparation method of 2,4-dichlorophenoxyacetic acid and a salt thereof, wherein the preparation method includes the following steps: S1) carrying out a reaction of phenol andchloracetic ester under alkaline conditions to obtain phenoxyacetic ester; S2) carrying out selective chlorination reaction of the phenoxyacetic ester with a chlorinating agent under the action of acatalyst A and a catalyst B to obtain 2,4-dichlorophenoxyacetic ester, wherein the catalyst A is Lewis acid, and the catalyst B is C5-22 thioethers, thiazoles, isothiazoles and thiophenes or halogenated derivatives thereof; and S3) carrying out hydrolysis reaction of 2,4-dichlorophenoxyacetic ester under acidic conditions to obtain 2,4-dichlorophenoxyacetic acid; or after 2,4-dichlorophenoxyaceticester is obtained, carrying out an alkaline hydrolysis reaction with an alkaline compound to obtain 2,4-dichlorophenoxyacetate. The production and use of 2,4-dichlorophenol with unpleasant odor are avoided, the production of dioxins is eliminated, the yield of products is improved, and the output of three wastes is greatly reduced.
Preparation method of phenoxycarboxylic acid choline salt
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Paragraph 0063; 0065, (2019/01/08)
The invention provides a preparation method of a phenoxycarboxylic acid choline salt, wherein the preparation method includes the steps: S1, carrying out condensation reaction of phenol or o-cresol with chlorocarboxylic ester in the presence of alkaline substances to obtain phenoxycarboxylic ester; S2, carrying out selective chlorination of the phenoxycarboxylic ester with a chlorinating agent inthe presence of a first catalyst and a second catalyst to obtain chlorobenzoxycarboxylic ester; and S3, after reaction of trimethylamine with ethylene oxide, adding the chlorophenoxycarboxylic acid ester, and carrying out alkaline hydrolysis reaction to obtain the phenoxycarboxylic acid choline salt. Compared with a conventional synthesis technology, the preparation method effectively avoids the production and use of chlorophenols with unpleasant odor, radically eliminates the production of highly toxic dioxins, and greatly improves the product quality and the operation environment of the production site; with phenol as the raw material, through condensation, selective chlorination and alkaline hydrolysis, the high-quality phenoxycarboxylic acid choline salt is obtained, the loss of effective ingredients is effectively avoided and the yield of the product is increased.
A method for preparing 2, 4 - dichlorophenoxyacetic acid (by machine translation)
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Paragraph 0055; 0056, (2018/09/08)
The invention provides a 2, 4 - dichlorophenoxyacetic acid preparation method, comprising: A) a halogenated acetic acid with the monoester should be halogenated acetate; phenol with alkali reaction to obtain the phenoxide; B) halogenated acetate and phenol salt reaction to obtain the phenoxyacetic acid ester; C) phenoxyacetic acid ester under the effects of catalyst chloride to obtain 2, 4 - dichlorophenoxy ester; said catalyst selected from iron trichloride, aluminum trichloride, boron trifluoride, five [...], trifluoromethyl sulfonate, aluminum oxide, ferric oxide, boron trioxide, niobium pentoxide, diphenyl ether, diphenyl sulfide, benzoin two sulfide, dimethyl sulfide and dimethyl sulfide in one or several of the D) 2, 4 - dichlorophenoxy ester hydrolysis to obtain 2, 4 - dichloro acid. This invention adopts the specific reaction routes and chlorinated using a specific catalyst, good reaction selectivity, few by-products, high yield. (by machine translation)
Preparation method and application of composition of 2,4-dichlorophenoxyacetic acid and 2,4-dichlorophenoxyacetate
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Paragraph 0102; 0103, (2018/09/08)
The invention provides a preparation method for a composition of 2,4-dichlorophenoxyacetic acid and 2,4-dichlorophenoxyacetate. The preparation method comprises the following steps: reacting halogenated acetate with 2,4-dichlorophenate so as to obtain 2,4-dichlorophenoxyacetate; and directionally hydrolyzing 2,4-dichlorophenoxyacetate prepared in the previous step to obtain the composition of 2,4-dichlorophenoxyacetic acid and 2,4-dichlorophenoxyacetate. According to the invention, a process route is adjusted and creative improvement is made from the foundation; halogenated acetate reacts with2,4-dichlorophenate so as to prepare 2,4-dichlorophenoxyacetate, and directional hydrolysis is carried out so as to obtain the composition of 2,4-dichlorophenoxyacetic acid and 2,4-dichlorophenoxyacetate. The composition of 2,4-dichlorophenoxyacetic acid and 2,4-dichlorophenoxyacetate of the invention has excellent quality, high stability and good drug effect.
Preparation method for 2,4-dichlorophenol, and preparation method for 2,4-dichlorophenolate
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Paragraph 0069; 0070, (2018/09/08)
The invention provides a preparation method for 2,4-dichlorophenol. The preparation method comprises the following steps: S1) mixing an initiator, phenol and a promoter in an organic solvent and carrying out chlorination under low temperature conditions to obtain the chlorination tail gas of phenol and a reaction solution, wherein the initiator is sulfuryl chloride, and the promoter is an ether compound; S2) mixing the chlorination tail gas of phenol with chlorine gas for a reaction to obtain sulfuryl chloride; and S3) mixing the sulfuryl chloride with the reaction solution and carrying out chlorination to obtain the chlorination tail gas of phenol and 2,4-dichlorophenol. Compared with the prior art, the invention has the following advantages: since chlorine gas is used as an initial chlorination raw material and continuously produces sulfuryl chloride through a reaction with sulfur dioxide in the chlorination tail gas of phenol, and then the sulfuryl chloride is continuously added into the reaction solution to obtain 2,4-dichlorophenol, so the preparation method has the advantages of high selectivity, low cost, high yield and simple flow due to adoption of continuous reaction andtail gas recycling flow; moreover, the reaction is carried out under low temperature conditions, so selectivity is improved; and the promoter is used, so a reaction rate is increased.
A method for preparing 2, 4 - dichlorophenoxyacetic acid (by machine translation)
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Paragraph 0044; 0045, (2018/09/08)
The invention provides a 2, 4 - dichlorophenoxyacetic acid preparation method, comprises the following steps: A) halogenated acetate with 2, 4 - dichlorophen salt reaction, to obtain 2, 4 - dichlorophenoxy ester; B) 2, 4 - dichlorophenoxy ester under the effects of catalyst hydrolysis reaction, to obtain 2, 4 - dichloro acid; said catalyst is selected from a polyether, a crown ether, quaternary ammonium salt, tertiary amine, [...], pyridine, titanate, inorganic acid, in organic acid one or more. The invention by halogenated acetate with 2, 4 - dichlorophen salt obtained by reaction of 2, 4 - dichlorophenoxy ester, and then in particular under the action of catalyst by hydrolysis reaction of the 2, 4 - dichloro acid. The invention specific reaction line combined with a specific catalyst such that the final preparation to obtain 2, 4 - dichlorophenoxyacetic acid purity and yield is relatively high, few by-products, the reaction route is simple, and is favorable for application. (by machine translation)
Preparation method for 2,4-dichlorophenoxyacetic acid
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Paragraph 0050; 0051; 0057, (2018/09/08)
The invention provides a preparation method for 2,4-dichlorophenoxyacetic acid. The preparation method comprises the following steps: A) reacting C2 or above-C2 alcohol with halogenated acetic acid soas to obtain halogenated acetate; B) reacting halogenated acetic acid with 2,4-dichlorophenolate so as to obtain 2,4-dichlorophenoxyacetate; and C) hydrolyzing 2,4-dichlorophenoxyacetate so as to obtain 2,4-dichlorophenoxyacetic acid. According to the invention, C2 or above-C2 alcohol reacts with halogenated acetic acid to obtain a halogenated acetate intermediate, the intermediate has good stability, few reaction by-products are produced, and high yield is realized; then the intermediate further reacts with 2,4-dichlorophenolate to obtain 2,4-dichlorophenoxyacetate; and finally, 2,4-dichlorophenoxyacetate is hydrolyzed to obtain 2,4-dichlorophenoxyacetic acid. Through a specific reaction route of the invention, the finally prepared 2,4-dichlorophenoxyacetic acid has high purity and yield, few by-products are produced, the reaction route is simple, and the application of the preparation method is facilitated.
