31881-89-7Relevant articles and documents
Synthesis method of 3, 5-difluorophenol
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Paragraph 0082-0089, (2021/04/07)
The invention discloses a synthetic method of 3, 5-difluorophenol, and belongs to the technical field of chemical synthesis. According to the method, 3,5-difluorophenolate is obtained through a one-pot reaction of 2,4,6-trifluorobenzoic acid in a solvent under the action of alkali, 3,5-difluorophenol is obtained after acid regulation and dissociation, and the method has the advantages of cheap and easily available raw materials, short synthesis steps, simple operation, mild reaction conditions, high synthesis yield, good product quality, suitability for industrial production and the like. According to the method, cheap and easily available pentachloronitrile is taken as a raw material, 2, 4, 6-trifluoro-3, 5-dichlorobenzonitrile is obtained through a fluorination reaction, 2, 4, 6-trifluoro-3, 5-dichlorobenzoic acid is obtained through a hydrolysis reaction, and finally, the raw material 2, 4, 6-trifluoro-3, 5-dichlorobenzoic acid is synthesized through a selective dechlorination reaction, so that simple, cheap and efficient preparation of the raw material 2, 4, 6-trifluorobenzoic acid is realized, and the industrial application value of the synthesis process is improved.
PROCESS FOR PREPARATION OF 2,4,6-TRIFLUOROBENZOIC ACID
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Page/Page column 9, (2021/08/14)
The present invention provides a process for the preparation of 2,4,6-trifluorobenzoic acid, having less than 0.05% of 2,6-difluorobenzoic acid and/or 2,4-difluorobenzoic acid impurities. The 2,4,6-trifluorobenzoic acid is crucial and an important raw material for preparing the photosensitizers, medicines and pesticides, and also finds applications in pharmaceutical and agrochemical industries.
Preparation method of 2,4,6-trifluorobenzylamine
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Paragraph 0043; 0045; 0046; 0048; 0050, (2018/03/24)
The invention provides a preparation method of 2,4,6-trifluorobenzylamine. The preparation method comprises the following steps: S1, by taking pentachloro benzonitrile as a starting material, adding the pentachloro benzonitrile into anhydrous potassium fluoride for fluorination reaction in a first organic solvent, thus obtaining 3,5-dichloro-2,4,6-trifluoro-cyanophenyl; S2a, adding the 3,5-dichloro-2,4,6-trifluoro-cyanophenyl prepared in the step S1 into a second organic solvent, adding organic alkali, feeding hydrogen, and carrying out dehydrochlorination reaction under the action of a firstcatalyst, thus obtaining 2,4,6-trifluoro-cyanophenyl serving as an intermediate; S3, adding the 2,4,6-trifluoro-cyanophenyl prepared in the step S2a into a third organic solvent, adding acid, feedinghydrogen, and reducing the 2,4,6-trifluoro-cyanophenyl serving as the intermediate through a cyanogroup under the action of a second catalyst, thus obtaining 2,4,6-trifluorobenzylamine. By the adoption of the technical scheme, the preparation method has the advantages that steps of a synthesis route are simple and short, conditions are mild, operation is simple and convenient, the raw materials are low in cost and readily available, and the production cost is low; the catalysts and solvents can be recycled for use, so that pollution is reduced; the preparation method is environmentally friendly and suitable for industrial large-scale production.
