611-06-3Relevant articles and documents
Novel preparation method of 2, 4, 5-trifluorophenylacetic acid
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Paragraph 0037; 0075-0077; 0097-0100; 0102-0103; 0105-0108, (2021/06/23)
The invention discloses a novel preparation method of 2, 4, 5-trifluorophenylacetic acid, which belongs to the technical field of preparation of medical intermediates, and comprises the following preparation steps: carrying out nitration reaction on sulfuric acid and m-dichlorobenzene to obtain an intermediate II; adding the intermediate II, a phase transfer catalyst and potassium fluoride into an aprotic solvent to obtain an intermediate III; performing hydrogenation reaction on the intermediate III to obtain an intermediate IV; carrying out diazotization reaction on the intermediate IV, nitrosyl sulfuric acid and sodium fluoborate to obtain an intermediate V; performing cracking reaction on the intermediate V to obtain an intermediate VI; carrying out reduction reaction on the intermediate VI, and then carrying out bromination reaction on the intermediate VI and liquid bromine to obtain an intermediate VII; subjecting the intermediate VII to a substitution reaction with diethyl malonate, and obtaining 2, 4, 5-trifluorophenylacetic acid after hydrolysis and purification. A novel synthesis route is provided, the problem that technological operation is tedious is solved, the requirements for reaction and operation conditions are low, anhydrous and oxygen-free reaction conditions are not needed, the method is suitable for industrial production, and the yield and purity are greatly improved.
Method for catalytically synthesizing 2, 4-dichloronitrobenzene by adopting tetraphenylphosphine iodide
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Paragraph 0021-0035, (2021/07/10)
The invention discloses a method for catalytically synthesizing 2, 4-dichloronitrobenzene by adopting tetraphenylphosphine iodide, and relates to the technical field of preparation of 2, 4-dichloronitrobenzene. The method specifically comprises the follow
Efficient synthesis method of meta-fluoranisole (by machine translation)
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Paragraph 0026; 0031; 0036; 0041; 0046; 0051; 0056; 0061, (2020/06/05)
The method is characterized by comprising the following steps: taking m-chloronitrobenzene as a raw material, carrying out high-temperature chlorination reaction, nitration reaction and fluorination reaction to obtain 2,4 - 2,4 -difluorobenzene and carrying out a methoxylation reaction with m-difluorobenzene as a raw material and carrying out methoxylation reaction to obtain m-fluorobenzyl ether; and the hydrogenation catalyst is a porous alumina loaded NiO-Co222O3-MoOO3 composite catalyst. The method disclosed by the invention is simple in process and high in product yield. (by machine translation)