- Synthesis method of 2, 4, 5-trifluoro-3-methoxybenzoyl chloride
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The invention discloses a synthesis method of 2, 4, 5-trifluoro-3-methoxybenzoyl chloride. The method comprises the following steps of: (1) using a metal halide as a catalyst, putting N-methyltetrafluorophthalimide in an alkaline environment, and carrying out hydroxylation reaction to obtain a sodium salt of 4-hydroxy-3, 5, 6-trifluorophthalic acid; (2) adding acid into the reaction system, and carrying out decarboxylation reaction to obtain 2, 4, 5-trifluoro-3-hydroxybenzoic acid; (3) sequentially adding a methylation reagent and acid into the reaction system under an alkaline condition, andcarrying out methylation reaction and acidification reaction to obtain 2, 4, 5-trifluoro-3-methoxybenzoic acid; and (4) mixing the 2, 4, 5-trifluoro-3-methoxybenzoic acid with thionyl chloride, and carrying out acylation reaction so as to obtain the 2, 4, 5-trifluoro-3-methoxybenzoyl chloride. The synthesis method disclosed by the invention is short in route, small in alkali dosage and few in sidereaction, the total molar yield of the reaction reaches 82.5%, and the purity of the product reaches 99.6% or above.
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Paragraph 0053; 0059-0062; 0073; 0077-0078; 0083; 0087-0088
(2020/09/16)
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- One-pot process for preparing 2,trifluoro -3 - methoxybenzoic acid (by machine translation)
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The method comprises the following steps: obtaining -3 - hydroxyl salt 4 - and -3 trifluoroortho-phthalate; and the method comprises the following steps: taking a metal halide as a catalyst, putting N - methyltetrafluoro phthalimide into a basic environment, and obtaining the 5,6 -hydroxy salt 4 - and -3 trifluoroortho-benzoate through hydrolysis defluorination and hydroxylation reaction 5,6 . The raw material cost is low, the process route is short, 4 - hydroxyl salt -3 and 5,6 -trifluoroortho-phthalate are synthesized only by about 8 - 10 hours, the base is reduced by 50% or more, the side reaction is less or complete, 85%, and the product purity can reach above 99.8%. (by machine translation)
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Paragraph 0056; 0062-0065; 0072; 0076; 0077; 0080; 0084-0085
(2020/09/23)
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- Preparation method of 2,4,5-trifluoro-3-methoxybenzoyl chloride and intermediate thereof
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The invention discloses a preparation method of 2,4,5-trifluoro-3-methoxybenzoyl chloride and intermediate thereof. The preparation method of 2,4,5-trifluoro-3-methoxybenzoyl chloride comprises the following steps: by taking tetrafluorophthalic acid as a raw material, carrying out defluorination hydroxylation and acidification decarboxylation to obtain 2,4,5-trifluoro-3-hydroxybenzoic acid, thenreacting with dimethyl carbonate to obtain 2,4,5-trifluoro-3-methoxybenzoic acid, and finally carrying out acylating chlorination to obtain 2,4,5-trifluoro-3-methoxybenzoyl chloride. The preparation process is simple, the total reaction yield is high, the product quality is good, the process route is environment-friendly, and the method has a good industrial application prospect.
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Paragraph 0034; 0045; 0046; 0049-0064
(2020/07/02)
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- Synthesis method of gatifloxacin cyclic ester
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The invention belongs to a production process of a pharmaceutical intermediate, and particularly discloses a synthesis method of gatifloxacin cyclic ester. The synthesis method comprises the followingsteps: performing hydrolysis, decarboxylation and methylation on 3, 4, 5, 6-tetrafluoro-N-methylphthalimide serving as a starting material to obtain 2,4,5-trifluoro-3-methoxybenzoyl chloride, coupling the 2,4,5-trifluoro-3-methoxybenzoyl chloride with N,N-ethyl dimethylaminoacrylate, then replacing with cyclopropylamine, and finally performing cyclization to produce the gatifloxacin cyclic esterunder the action of DMF and potassium fluoride. The reaction route is short, the raw materials are wide in source; furthermore, the reaction conditions are mild and easy to operate and control, whichreduces the consumption of the raw materials, facilitates the post-treatment and reduces the cost; potassium fluoride used instead of potassium carbonate in the reaction can not only reduce productionof exhaust gas, but also make the used potassium fluoride used continuously through adjustment by potassium hydroxide, and the cost is further reduced.
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Paragraph 0031; 0039-0041; 0045-0047; 0051-0053; 0067-0070
(2019/11/04)
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- The site-selective functionalization of halogen-bearing phenols: An exercise in diversity-oriented organometallic synthesis
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The organometallic approach to diversity-oriented organic synthesis was subjected to a further test, this time in the phenol series. The model compounds selected were 2,3,6-trifluorophenol, the three isomers of (trifluoromethoxy) phenol and the three isomers of chlorophenol. A combination of optionally site selective metalations and protective group-controlled metalations enabled the selective generation of several isomeric intermediates in each case and their subsequent conversion into functionalized derivatives, in particular hydroxybenzoic acids.
- Marzi, Elena,Schlosser, Manfred
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p. 3393 - 3401
(2007/10/03)
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- Trifluorohydroxyaromatic acid and preparation thereof
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There are disclosed 2,4,5-Trifluoro-3-hydroxybenzoic acid represented by the following formula (I): STR1 and a salt thereof and a process for preparing the same. Further, there is disclosed a process for preparing 3,5,6-trifluoro-4-hydroxyphthalic acid, which is employed for preparing the above compound.
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