- Difluoromethylation of Phenols and Thiophenols with the S-(Difluo-romethyl)sulfonium Salt: Reaction, Scope, and Mechanistic Study
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A facile and practical approach for the difluoromethylation of phenols and thiophenols was described. Making use of the recently developed bench-stable S-(difluoromethyl)sulfonium salt as the difluorocarbene precursor, a wide variety of diversely functionalized phenols and thiophenols were readily converted to their corresponding aryl difluoromethyl ethers in good to excellent yields in the presence of lithium hydroxide. Chemoselectivity of various O,S-nucleophiles toward difluorocarbene was systematically studied, suggesting the reactivity order ArS- > RS-, ArO- > ROH > RO-, ArSH, ArOH, RSH.
- Liu, Guo-Kai,Qin, Wen-Bing,Li, Xin,Lin, Li-Ting,Wong, Henry N. C.
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p. 15948 - 15957
(2019/11/16)
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- Difluoromethoxy substituted diphenylethane and trans-distyrene derivative and preparation method and application thereof
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The invention discloses a difluoromethoxy substituted diphenylethane and trans-distyrene derivative and a preparation method and application thereof. The 4 prime bit of B aromatic ring of diphenylethane/stilbene is subjected to chemical structural modification with difluoromethoxy, and meanwhile, the 3 prime bit is modified into substituents of nitro, amino or hydroxyl and the like. The difluoromethoxy substituted diphenylethane and trans-distyrene derivative is high in antitumor activity in vitro, physical, chemical and biological properties are changed by introduction of difluromethylation, and obvious inhibitory effect on tumor cells is achieved.
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Paragraph 0027; 0028
(2017/12/14)
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- Nitro imidazole heterocyclic compound and its in the preparation of medicine for treating tuberculosis the application of the
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The invention relates to a novel nitroimidazole heterocyclic compound and an application of the nitroimidazole heterocyclic compound in preparation of a medicine for treating tuberculosis. The nitroimidazole heterocyclic compound of the present invention has dual function mechanism, can inhibit the protein synthesis of tuberculosis mycobacterium and synthesis of cell wall mycolic acid, has strong activity on pathogen tuberculosis mycobacterium capable of causing tuberculosis, and has high bioavailability.
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Paragraph 0061; 0062
(2016/10/10)
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- Decarboxylative Trifluoromethylating Reagent [Cu(O2CCF3)(phen)] and Difluorocarbene Precursor [Cu(phen)2][O2CCF2Cl]
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This article describes the new economic decarboxylative trifluoromethylating reagent [Cu(phen)(O2CCF3)] (1; phen=1,10-phenanthroline) and the efficient difluorocarbene precursor [Cu(phen)2][O2CCF2Cl] (2). Treatment of copper tert-butoxide with phen and subsequent addition of trifluoroacetic acid or chlorodifluoroacetic acid afforded air-stable complexes 1 and 2, respectively, which were characterized by X-ray crystallography. The copper(I) ion in 1 is coordinated by a bidentate phen ligand, a monodentate trifluoroacetate group, and a molecule of CH3CN in a distorted tetrahedral coordination geometry. The molecular structure of 2 adopts an ionic form that consists of a [Cu(phen)2]+ cation and a chlorodifluoroacetate anion. Complex 1 reacted with a variety of aryl and heteroaryl halides to form trifluoromethyl (hetero)arenes in good yields. The corresponding Hammett plot exhibited a linear relationship and a reaction parameter (ρ)=+0.56±0.02, which indicated that the trifluoromethylation reaction proceeded via a nucleophilic reactive species. Complex 2 reacts with phenols to produce aryl difluoromethyl ethers in modest-to-excellent yields. Mechanistic investigations revealed that the difluoromethylation reaction proceeds by initial copper-mediated formation of difluorocarbene and subsequent concerted addition of difluorocarbene to the phenol to form a three-center transition state.
- Lin, Xiaoxi,Hou, Chuanqi,Li, Haohong,Weng, Zhiqiang
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supporting information
p. 2075 - 2084
(2016/02/12)
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- SYNTHESIS OF DIFLUOROMETHYL ETHERS AND SULFIDES
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The synthesis of difluoromethyl ethers and sulfides with a simple, non-ozone- depleting reagent is described. The difluoromethylation of phenols with this reagent occurs at room temperature within minutes with exceptional functional group tolerance. The mild conditions makes possible tandem processes for the conversion of aryl boronic acids, aryl halides and arenes to difluoromethyl ethers. Mechanistic studies support a reaction pathway involving nucleophilic attack of the phenolate to difluorocarbene.
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Paragraph 00166-00167
(2014/07/22)
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- Synthesis of gem-difluorocyclopropa(e)nes and O-, S-, N-, and P-difluoromethylated compounds with TMSCF2Br
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Two-in-one: Me3SiCF2Br is an efficient difluorocarbene source and is compatible with both neutral and aqueous basic conditions. Bromide-ion-initiated [2+1] cycloaddition with alkenes/alkynes and hydroxide ion promoted α-addition with (thio)phenols, (thio)alcohols, sulfinates, heterocyclic amines, and H-phosphine oxides give the corresponding gem-difluorinated compounds with broad functional-group tolerance. Copyright
- Li, Lingchun,Wang, Fei,Ni, Chuanfa,Hu, Jinbo
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supporting information
p. 12390 - 12394
(2013/12/04)
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- Fluoroalkoxycombretastatin Derivatives, Method For Producing the Same and Use Thereof
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Combretastatin derivatives of formula (I), preparation and use thereof are disclosed, wherein: Rf is alkyl with 1-8 carbon atoms and 1-17 fluorine atoms, R is amino, substituted amino, hydroxyl, nitro, halo, alkyloxy, phosphate or amino acid side chain. Said derivatives have a capability to inhibit the polymerization of microtubules and are useful in treatment against tumor and neovascularization.
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Page/Page column 7-8
(2009/01/20)
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- AZOLE-BASED PHOSPHODIESTERASE INHIBITORS
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The present invention relates to phosphodiesterase (PDE) type IV selective inhibitors. Processes for the preparation of disclosed compounds of Formula (I), pharmaceutical compositions containing the compounds described herein and their use as PDE type IV selective inhibitors are provided.
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Page/Page column 45
(2010/11/24)
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- SYNTHESIS AND REACTIONS OF DIFLUOROMETHOXY- AND DIFLUOROCHLOROMETHOXY DERIVATIVES OF BENZENE
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Difluoromethoxybenzaldehydes were synthesized by difluoromethylation of aromatic o- and p-hydroxyaldehydes by chladone-22 in alkaline medium.Chlorination of the difluoromethoxybenzene derivatives under illumination gave difluorochloromethoxy benzene with various function groups (F, Cl, CN, COCl, COOH).The values of the ?-constants of the OCF2Cl group have been determined.In its electronic characteristics it is similar to the OCF3 group.
- Shelyazhenko, S. V.,Fialkov, Yu. A.,Yagupol'skii, L. M.
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p. 1317 - 1324
(2007/10/02)
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- IMPROVEMENT OF THE SYNTHESIS OF ARYL DIFLUOROMETHYL ETHERS AND THIOEHTERS BY USING A SOLID-LIQUID PHASE-TRANSFER TECHNIQUE
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A new solid-liquid phase-transfer technique has been used to synthesize aryl difluoromethyl ehters and thioethers.Phenols (or thiophenols) and chlorodifuoromethane, dissolved in a cheap aprotic solvent of low polarity, are contacted with solid sodium hydroxide in the presence of a catalytic amount of tris-(3,6-dioxaheptyl)amine.The work-up of the reaction mixtures is very simple.Although yields are similar in both homogeneous and heterogeneous procedures using phenols, improved yields are obtained for thiophenols when using phase-transfer conditions.
- Langlois, Bernard R.
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p. 247 - 262
(2007/10/02)
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