- Preparation method of 2, 4-dichloro-5-fluoroacetophenone
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The invention provides a preparation method of 2, 4-dichloro-5-fluoroacetophenone. The method comprises the following steps: by taking 2, 4-dichlorofluorobenzene as a raw material, carrying out Friedel-Crafts reaction on 2, 4-dichlorofluorobenzene and vinylidene chloride in the presence of anhydrous aluminum chloride and protonic acid at the same time to generate 1-(1, 1-dichloroethyl)-2, 4-dichloro-5-fluoroacetophenone benzene, carrying out hydrolysis reaction on the intermediate product under the catalysis of Lewis acid to generate 2, 4-dichloro-5-fluoroacetophenone and hydrogen chloride, adding a proper amount of water for layering after the reaction is finished, and rectifying an organic layer to obtain the product. According to the method, the cost of raw materials and auxiliary materials is greatly reduced, the post-treatment pressure is relieved, the yield can reach 85% or above, and the method belongs to the technical field of organic chemical industry.
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Paragraph 0015-0016; 0017; 0035-0037
(2021/08/14)
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- O-dichlorobenzene with a quinolone drugs for coproduction method of key intermediate
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The invention relates to the field of methods for preparing medicinal intermediates, in particular to the field of methods for preparing key intermediates of quinolone medicines, and develops a method for coproducing the key intermediates of the quinolone medicines by using o-dichlorobenzene as a raw material. The method comprises the following steps of: nitrifying the o-dichlorobenzene serving as the raw material, and performing distillation, purification and stepwise crystallization to obtain 2,3-dichloronitrobenzene and 3,4-dichloronitrobenzene; performing fluoridation on the 2,3-dichloronitrobenzene to obtain 3-chloro-2-fluoronitrobenzene, performing chlorination to obtain 2,6-dichlorofluorobenzene, performing nitration to obtain 1,3-dichloro-2-fluoro-4-nitrobenzene, and finally performing fluoridation to obtain 2,3,4-trifluoronitrobenzene; and performing fluoridation on the 2,3,4-trifluoronitrobenzene to obtain 3-chloro-4-fluoronitrobenzene, performing chlorination to obtain 1,3-dichloro-4-fluorobenzene, and finally performing acylation reaction on the 1,3-dichloro-4-fluorobenzene and acetylchloride to obtain 2,4-dichloro-5-fluoroacetophenone.
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- ANTIVIRAL AND ANTIMICROBIAL COMPOUNDS
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Disclosed are guanidine and biguanidine derivatives which have anti-viral and antibacterial activity. Also disclosed are pharmaceutical compositions containing such compounds as an active ingredient, and anti-viral and anti-bacterial methods utilizing such compounds. Methods of treating infections using the guanidine and biguanidine derivatives are also disclosed.
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Paragraph 0120; 0121
(2014/03/25)
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- A PROCESS FOR SYNTHESIS OF 2, 4-DICHLORO-5- FLUOROACETOPHENONE (DCFA)
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A process for synthesis of 2,4-dichloro-5-fluoro acetophenone (DCFA) is disclosed. The process comprises first reacting 3,4-dichloronitrobenzene with potassium fluoride having bulk density in the range of 0.2 to 1.3, to form a fluorinated intermediate product, then reacting the intermediate product with chlorine to form dichlorofluorobenzene and finally acylating dichlorofluorobenzene using an acylating agent to form a mixture containing DCFA along with impurities, followed by purification and enrichment of DCFA in the mixture by melt crystallization.
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Page/Page column 20-21
(2010/07/10)
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- A novel approach to Finafloxacin hydrochloride (BAY35-3377)
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Finafloxacin hydrochloride, an important clinical compound was synthesized by a novel synthetic approach. An active intermediate ethyl 7-chloro-8-cyano-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylate 19 was prepared by a new route. The chiral (S,S′)-N-Boc 10 was derived from protected pyrrolidine and the absolute stereochemistry was established by X-ray analysis.
- Hong, Jian,Zhang, Zonghua,Lei, Huoxing,Cheng, Haiying,Hu, Yufang,Yang, Wanliang,Liang, Yinglin,Das, Debasis,Chen, Shu-Hui,Li, Ge
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body text
p. 2525 - 2528
(2009/09/06)
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- Synthesis of functionalised acetophenone
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Nickel catalysed Heck arylation of the electron-rich olefin n-butyl vinyl ether with a wide variety of aryl bromides has been accomplished in the ionic liquid [bmim][BF4], affording an efficient green chemistry synthetic procedure for preparing functionalised acetophenone. The reaction gave a high regioselectivity and high yield without the need for the costely or toxic halide scavengers, leading predominantly to a branch-arylated α-product.
- Sun, Li,Pei, Wen,Shen, Chen
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p. 388 - 389
(2007/10/03)
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- Compounds with antibacterial and antiparasitic properties
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There are provided novel compounds which have both antibacterial and antiparasitic properties, thereby reducing the need for using several compounds in combined antibacterial and antiparasitic treatment of livestock. The present novel compounds are especially well suited for treatment of coccidiosis, and they are represented by general formula (I) wherein R1-R6, X and A are as defined in the specification.
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Page/Page column 25-26
(2008/06/13)
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- Pyridinyl-quinolone compounds, their preparation and use
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Fluorinated 1-cyclopropyl-7-(substituted-pyridinyl)-1,4-dihydro-4-oxo-3-quinolinecarboxylic acids of the formula STR1 wherein R is hydrogen, R' and R" are hydrogen or fluoro, or other groups and Z is 3- or 4-pyridinyl substituted by alkyl groups or substituted alkyl groups, are superior antibacterial agents. They are prepared via a coupling reaction between the corresponding esters (R=alkyl) having a halo group in the 7-position and a substituted (trialkylstannyl)pyridine.
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- 7-(substituted)piperazinyl-1-ethyl-6-fluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylic acids
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7-(substituted)piperazinyl-1-ethyl-6-fluoro-4-oxo-3-quinolinecarboxylic acids, the pharmacologically acceptable salts thereof, compositions containing them, processes and intermediates for producing them, and methods of using them to treat bacterial infections in warm-blooded animals.
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