3035-67-4Relevant academic research and scientific papers
Synthesis method of substituted phenoxyacetate compound
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Paragraph 0065; 0066; 0067, (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 acid and salt thereof
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, (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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, (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 0012; 0092; 0094; 0095, (2018/09/08)
The invention provides a 2, 4 - dichlorophenoxyacetic acid preparation method, comprises the following steps, first alcohol and a halogenated acetic acid after the reaction, to obtain halogenated acetate; the 2, 4 - dichlorophen after reaction with the alkali, to obtain 2, 4 - II [...]; then the above-mentioned step to obtain the halo acetate with 2, 4 - dichlorophen salt, to obtain 2, 4 - dichlorophenoxy ester; then obtained the above-mentioned step 2, 4 - dichlorophenoxy ester hydrolytic reaction, to obtain the 2, 4 - dichloro acid and alcohol; finally the above-mentioned step returns mellowly obtained is used in the aforesaid step, recycling; the alcohol is C atom number greater than or equal to 2 alcohol. The invention adjusts the process route, from the improved on the basis of, the reaction process is cleaning, of the small amount of waste water, hydrolysis few by-products, high purity of the product, the conversion and yield higher; and process raw materials can be recycled, is suitable for large-scale industrial production. (by machine translation)
Preparation method for 2,4-dichlorophenoxyacetic acid
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Paragraph 0055; 0057; 0058, (2018/09/08)
The invention provides a preparation method for 2,4-dichlorophenoxyacetic acid, belonging to the technical field of organic synthesis. The preparation method comprises the following steps: a) reactinghalogenated acetate with 2,4-dichlorophenolate in the presence of a phase-transfer catalyst so as to obtain 2,4-dichlorophenoxyacetate; and b) hydrolyzing 2,4-dichlorophenoxyacetate so as to obtain 2,4-dichlorophenoxyacetic acid. According to the invention, oil-phase halogenated acetate reacts with 2,4-dichlorophenolate under the action of the phase-transfer catalyst to prepare 2,4-dichlorophenoxyacetate, and then 2,4-dichlorophenoxyacetate is hydrolyzed to obtain 2,4-dichlorophenoxyacetic acid and corresponding alcohols. Under the action of the phase-transfer catalyst, few hydrolysis by-products are produced during a reaction, fast reaction speed and high conversion rate and yield are obtained, and the amount of produced waste water is low; so industrial application of the preparation method can be easily implemented.
A method for preparing 2, 4 - dichlorophenoxyacetic acid (by machine translation)
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, (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 of chlorophenoxycarboxylic ester
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Paragraph 0071; 0073; 0075; 0077; 0078; 0080; 0099; 0101, (2019/01/08)
The invention provides a preparation method of chlorophenoxycarboxylic ester, wherein the preparation method includes the following steps: S1) carrying out 2-site and/or 4-site selective chlorinationreaction of phenoxycarboxylic ester with a chlorinating agent under the action of a catalyst A and a catalyst B to obtain chlorophenoxycarboxylic ester, wherein the catalyst A is Lewis acid, the catalyst B has the following structural formula of R1'-S-R2', and the phenoxycarboxylic ester has any structure represented by the formulas I-IV; and S2) carrying out transesterification reaction of chlorophenoxycarboxylic ester and alcohol under the action of a catalyst to obtain long-chain chlorophenoxycarboxylic ester, wherein the alcohol has the molecular formula of R2OH, and R2 is C4-20 alkyl or cycloalkyl. The method improves the yield and purity of chlorophenoxycarboxylic ester by redesigning of the process route and fine screening of the catalysts and the chlorinating agent. The content ofthe obtained chlorophenoxycarboxylic ester can reach 98.5% or more and the yield can reach 98.5% or more.
Preparation method of chlorophenoxycarboxylic ester
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Paragraph 0088; 0090, (2019/01/08)
The invention provides a preparation method of chlorophenoxycarboxylic ester, wherein the preparation method includes the following steps: S1) carrying out 2-site and/or 4-site selective chlorinationreaction of phenoxycarboxylic ester with a chlorinating agent under the action of a catalyst A and a catalyst B to obtain chlorophenoxycarboxylic ester, wherein the catalyst A is Lewis acid, the catalyst B is C5-22 thiazoles, isothiazoles and thiophenes or halogenated derivatives thereof, and the phenoxycarboxylic ester has any structure represented by the formulas I-IV; and S2) carrying out transesterification reaction of chlorophenoxycarboxylic ester and alcohol under the action of a catalyst to obtain long-chain chlorophenoxycarboxylic ester, wherein the alcohol has the molecular formula ofR2OH, and R2 is C4-20 alkyl or cycloalkyl. The method improves the yield and purity of chlorophenoxycarboxylic ester by redesigning of the process route and fine screening of the catalysts and the chlorinating agent. The content of the obtained chlorophenoxycarboxylic ester can reach 98.5% or more and the yield can reach 98.5% or more.
Preparation method of chlorophenoxycarboxylic ester
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Paragraph 0061; 0062, (2019/01/06)
The invention provides a preparation method of chlorophenoxycarboxylic ester, wherein the preparation method includes the following steps: carrying out 2-site and/or 4-site selective chlorination reaction of phenoxycarboxylic ester with a chlorinating agent under the action of a catalyst A and a catalyst B to obtain chlorophenoxycarboxylic ester, wherein the catalyst A is Lewis acid, and the catalyst B is C5-22 thiazoles, isothiazoles and thiophenes or halogenated derivatives thereof. The method effectively improves the chlorination selectivity and avoids loss of effective ingredients by redesigning of the process route and fine screening of the catalysts and the chlorinating agent. The content of the obtained chlorophenoxycarboxylic ester can reach 98.5% or more and the yield can reach 99% or more.
Preparation method of chlorophenoxycarboxylic ester
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Paragraph 0072; 0073, (2019/01/08)
The invention provides a preparation method of chlorophenoxycarboxylic ester, wherein the preparation method includes the following steps: carrying out 2-site and/or 4-site selective chlorination reaction of phenoxycarboxylic ester with a chlorinating agent under the action of a catalyst A and a catalyst B to obtain chlorophenoxycarboxylic ester, wherein the catalyst A is Lewis acid, and the catalyst B has the following structural formula of R1'-S-R2'. The method effectively improves the chlorination selectivity and avoids loss of effective ingredients by redesigning of the process route and fine screening of the catalysts and the chlorinating agent. The content of the obtained chlorophenoxycarboxylic ester can reach 98.5% or more and the yield can reach 99% or more.
