875664-57-6Relevant articles and documents
Preparation method of 2,4,5-trifluorophenylacetic acid
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Paragraph 0040; 0042; 0078, (2021/05/29)
The invention belongs to the technical field of preparation of drug intermediates, and discloses a preparation method of 2,4,5-trifluorophenylacetic acid, wherein the preparation method comprises the steps: step 1, reacting raw materials, a quaternary ammonium salt catalyst, sulfolane and potassium fluoride to obtain a first intermediate; step 2, carrying out hydrogenation catalytic reaction on the first intermediate to obtain a second intermediate; step 3, carrying out salt forming reaction on the second intermediate and a fluorinating reagent, quenching, and carrying out diazotization reaction on the second intermediate and a sodium nitrite aqueous solution to obtain diazonium salt; step 4, carrying out high-temperature cracking on the diazonium salt, to obtain 2,4,5-trifluorotoluene; and step 5 to step 7, carrying out halogenation, cyanidation and hydrolysis reactions on 2,4,5-trifluorotoluene in sequence, and thus obtaining 2,4,5-trifluorophenylacetic acid. The raw materials adopted by the method are easy to obtain and low in cost, the yield of the corresponding product obtained in each step is high, and large-scale production of the 2,4,5-trifluorophenylacetic acid is facilitated.