657-35-2Relevant academic research and scientific papers
A HF Loaded Lewis-Acidic Aluminium Chlorofluoride for Hydrofluorination Reactions
Kervarec, Ma?va-Charlotte,Kemnitz, Erhard,Scholz, Gudrun,Rudi?, Svemir,Braun, Thomas,J?ger, Christian,Michalchuk, Adam A. L.,Emmerling, Franziska
, p. 7314 - 7322 (2020)
The very strong Lewis acid aluminium chlorofluoride (ACF) was loaded with anhydrous HF. The interaction between the surface of the catalyst and HF was investigated using a variety of characterization methods, which revealed the formation of polyfluorides. Moreover, the reactivity of the HF-loaded ACF towards the hydrofluorination of alkynes was studied.
Copper-Catalyzed Functionalization of Benzylic C-H Bonds with N-Fluorobenzenesulfonimide: Switch from C-N to C-F Bond Formation Promoted by a Redox Buffer and Br?nsted Base
Buss, Joshua A.,Golden, Dung L.,Stahl, Shannon S.,Vasilopoulos, Aristidis
supporting information, p. 5749 - 5752 (2020/10/02)
A copper catalyst in combination with N-fluorobenzenesulfonimide (NFSI) has been reported to functionalize benzylic C-H bonds to the corresponding benzylic sulfonimides via C-N coupling. Here, we reported a closely related Cu-catalyzed method with NFSI that instead leads to C-F coupling. This switch in selectivity arises from changes to the reaction conditions (Cu/ligand ratio, temperature, addition of base) and further benefits from inclusion of MeB(OH)2 in the reaction. MeB(OH)2 is shown to serve as a "redox buffer"in the reaction, responsible for rescuing inactive Cu(II) for continued promotion of fluorination reactivity.
METHOD FOR PRODUCING (FLUOROALKYL) ARENE
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Paragraph 0070; 0072; 0107-0110, (2018/08/28)
PROBLEM TO BE SOLVED: To provide a method for efficiently producing fluoroalkyl arene, which is important as synthetic raw materials for medicines and functional materials. SOLUTION: A fluoroalkyl arene is produced by the reaction between an aryl metal species represented by formula (2) and a fluoroalkyl halide represented by formula (3) in the presence of a cobalt compound and an ethylenediamine derivative. In the formula (2) shown in the following figure, R11-R15 independently represent H, a C1-C4 alkyl group or the like. In the formula (3): Y-Rf, Y is Cl or the like; Rf is a C2-C3 fluoroalkyl group. SELECTED DRAWING: None COPYRIGHT: (C)2016,JPOandINPIT
Copper-Mediated Aromatic 1,1-Difluoroethylation with (1,1-Difluoroethyl)trimethylsilane (TMSCF2CH3)
Li, Xinjin,Zhao, Jingwei,Wang, Yunze,Rong, Jian,Hu, Mingyou,Chen, Dingben,Xiao, Pan,Ni, Chuanfa,Wang, Limin,Hu, Jinbo
, p. 1789 - 1792 (2016/07/07)
A new method for the formation of 1,1-difluoroethyl copper species (“CuCF2CH3”) with 1,1-difluoroethylsilane (TMSCF2CH3) has been developed. The “CuCF2CH3” species can be applied to the efficient 1,1-difluoroethylation of diaryliodonium salts under mild conditions, affording (1,1-difluoroethyl)arenes in good to excellent yields. This convenient procedure tolerates a wide range of functional groups and thus serves as a practical synthetic tool for the introduction of CF2CH3 group(s) into complex molecules.
Cobalt/diamine-catalyzed 1,1-difluoroethylation and 2,2,2-trifluoroethylation of aryl Grignard reagents with corresponding fluoroalkyl halides
Ohtsuka, Yuhki,Yamakawa, Tetsu
, p. 96 - 102 (2016/04/05)
Cobalt/diamine-catalyzed 1,1-difluoroethylation and 2,2,2-trifluoroethylation of aryl Grignard reagents with 1,1-difluoroethyl and 2,2,2-trifluoroethyl halides were investigated. With regard to the 1,1-difluoroethylation, 1,2-bis(dimethylamino)-2-methylpropane, which has been rarely used in the cross-coupling reactions, gave the highest yield among the diamine ligands tested. In the 2,2,2-trifluoroethylation, trans-1,2-bis(dimethylamino)cyclohexane provided the desired products in satisfactory yields with not only 2,2,2-trifluoroethyl iodide but also chloride. This Co/diamine catalyst was also effective for the coupling with other partially fluorinated alkyl halides in the presence of appropriate diamine ligands.
Designer HF-Based fluorination reagent: Highly regioselective synthesis of fluoroalkenes and gem -difluoromethylene compounds from alkynes
Okoromoba, Otome E.,Han, Junbin,Hammond, Gerald B.,Xu, Bo
supporting information, p. 14381 - 14384 (2015/01/09)
Hydrogen fluoride (HF) and selected nonbasic and weakly coordinating (toward cationic metal) hydrogen-bond acceptors (e.g., DMPU) can form stable complexes through hydrogen bonding. The DMPU/HF complex is a new nucleophilic fluorination reagent that has high acidity and is compatible with cationic metal catalysts. The gold-catalyzed mono- and dihydrofluorination of alkynes using the DMPU/HF complex yields synthetically important fluoroalkenes and gem-difluoromethlylene compounds regioselectively.
Visible light-promoted metal-free C-H activation: Diarylketone-catalyzed selective benzylic mono- and difluorination
Xia, Ji-Bao,Zhu, Chen,Chen, Chuo
supporting information, p. 17494 - 17500 (2014/01/06)
We report herein an operationally simple method for the direct conversion of benzylic C-H groups to C-F. We show that visible light can activate diarylketones to abstract a benzylic hydrogen atom selectively. Adding a fluorine radical donor yields the benzylic fluoride and regenerates the catalyst. The selective formation of mono- and difluorination products can be achieved by catalyst control. 9-Fluorenone catalyzes benzylic C-H monofluorination, while xanthone catalyzes benzylic C-H difluorination. The scope and efficiency of this new C-H fluorination method are significantly better than those of the existing methods. This is also the first report of selective C-H gem-difluorination.
Method of Synthesis of Arylsulfur Trifluorides and Use as in situ Deoxofluorination Reagent
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Page/Page column 2; 3, (2012/04/11)
The invention is a method of synthesizing Arylsulfur Trifluorides, such as Fluolead, by reacting BR2 and KF (or suitable alkali metal fluoride) in acetonitrile (or other suitable solvent). The invention also comprises using the Fluolead (or its
Arylsulfur chlorotetrafluorides as useful fluorinating agents: Deoxo- and dethioxo-fluorinations
Umemoto, Teruo,Singh, Rajendra P.
experimental part, p. 17 - 27 (2012/09/07)
Usage of arylsulfur chlorotetrafluorides 1 as versatile deoxo- and dethioxo-fluorinating agents is described. There have been developed two convenient methods for the in situ preparation of reactive arylsulfur trifluorides 2 from 1. The one is reduction of 1 with a reducer such as pyridine to 2, and the other is disproportionation of 1 with a diaryl disulfide to 2 with evolution of chlorine gas. The latter method is a convenient way to get neat 2 from 1. The in situ prepared 2 fluorinates many kinds of substrates such as alcohols, aldehydes, ketones, diketones, and carboxylic acids to give the corresponding CF, CF2, CF2CF2, and CF 3 compounds in high yields. 2 also fluorinates various sulfur compounds including CS groups to give CF2, OCF2, CF 3, and OCF3 compounds in high yields. Reactions of 2 with diols or bis(trimethylsilyl) derivatives of diols or amino alcohols provided the corresponding deoxofluoro-arylsulfinylation products in high yields. In addition, it has been found that chlorotetrafluorides 1 directly and effectively react with the sulfur compounds to give the corresponding fluoro compounds in high yields. Since they are the intermediates for the production of industrially useful arylsulfur pentafluorides, arylsulfur chlorotetrafluorides 1, in particular, phenylsulfur chlorotetrafluoride (1a) are expected to find use as inexpensive and versatile deoxo- and dethioxo-fluorinating agents for the preparation of many organofluoro compounds.
Arylsulfur trifluorides: Improved method of synthesis and use as in situ deoxofluorination reagents
Xu, Wei,Martinez, Henry,Dolbier Jr., William R.
experimental part, p. 482 - 488 (2011/08/03)
Building on recent results of Umemoto and Winter, an improved method of synthesis of arylsulfur trifluorides, including the excellent, new deoxofluorination reagent Fluolead, is hereby reported. The method utilizes Br2 and KF as oxidizing and fluorinating reagents for efficient, high yield conversion of aryl disulfides and mercaptans to arylsulfur trifluorides. It has also been shown that both Fluolead and mesitylsulfur trifluoride may be generated in acetonitrile and used as in situ deoxofluorination reagents for conversion of either aldehydes or ketones to their respective gem-difluoro compounds. An analysis of the probable mechanism of action, including computational efforts, allows postulation of a rationale for the highly variable reactivities of different arylsulfur trifluorides as deoxofluorination reagents.
