93841-19-1Relevant academic research and scientific papers
Cathodic C-H Trifluoromethylation of Arenes and Heteroarenes Enabled by an in Situ-Generated Triflyltriethylammonium Complex
Cantillo, David,Jud, Wolfgang,Kappe, C. Oliver,Maljuric, Snjezana
supporting information, (2019/10/08)
While several trifluoromethylation reactions involving the electrochemical generation of CF3 radicals via anodic oxidation have been reported, the alternative cathodic, reductive radical generation has remained elusive. Herein, the first cathodic trifluoromethylation of arenes and heteroarenes is reported. The method is based on the electrochemical reduction of an unstable triflyltriethylammonium complex generated in situ from inexpensive triflyl chloride and triethylamine, which produces CF3 radicals that are trapped by the arenes on the cathode surface.
Introducing a new radical trifluoromethylation reagent
Sato, Azusa,Han, Jianlin,Ono, Taizo,Wzorek, Alicja,Ace?a, José Luis,Soloshonok, Vadim A.
supporting information, p. 5967 - 5970 (2015/03/30)
Perfluoro-3-ethyl-2,4-dimethyl-3-pentyl radical (PPFR) is a persistent radical stable at room temperature, but easily decomposes at 90 °C to produce a CF3 radical which is able to react with a variety of aromatic compounds to afford the corresponding trifluoromethyl derivatives, usually as mixtures of regioisomers in good to excellent overall yields.
Trifluoromethylation of aryl and heteroaryl halides with fluoroform-derived CuCF3: Scope, limitations, and mechanistic features
Lishchynskyi, Anton,Novikov, Maxim A.,Martin, Eddy,Escudero-Adan, Eduardo C.,Novak, Petr,Grushin, Vladimir V.
, p. 11126 - 11146 (2013/12/04)
Fluoroform-derived CuCF3 recently discovered in our group exhibits remarkably high reactivity toward aryl and heteroaryl halides, performing best in the absence of extra ligands. A broad variety of iodoarenes undergo smooth trifluoromethylation with the ligandless CuCF3 at 23-50 C to give the corresponding benzotrifluorides in nearly quantitative yield. A number of much less reactive aromatic bromides also have been trifluoromethylated, including pyridine, pyrimidine, pyrazine, and thiazole derivatives as well as aryl bromides bearing electron-withdrawing groups and/or ortho substituents. Only the most electrophilic chloroarenes can be trifluoromethylated, e.g., 2-chloronicotinic acid. Exceptionally high chemoselectivity of the reactions (no side-formation of arenes, biaryls, and C2F5 derivatives) has allowed for the isolation of a large number of trifluoromethylated products in high yield on a gram scale (up to 20 mmol). The CuCF3 reagent is destabilized by CuX coproduced in the reaction, the magnitude of the effect paralleling the Lewis acidity of CuX: CuCl > CuBr > CuI. While SNAr and SRN1 mechanisms are not operational, there is a well-pronounced ortho effect, i.e., the enhanced reactivity of ortho-substituted aryl halides 2-RC6H4X toward CuCF3. Intriguingly, this ortho-effect is observed for R = NO2, COOH, CHO, COOEt, COCH3, OCH3, and even CH3, but not for R = CN. The fluoroform-derived CuCF3 reagent and its reactions with haloarenes provide an unmatched combination of reactivity, selectivity, and low cost.
Silver-mediated trifluoromethylation of arenes using TMSCF3
Ye, Yingda,Lee, Shin Hee,Sanford, Melanie S.
supporting information; experimental part, p. 5464 - 5467 (2011/12/05)
The silver-mediated C-H trifluoromethylation of aromatic substrates using TMSCF3 is described. The development, optimization, and scope of these transformations are reported. AgCF3 intermediates are proposed.
Phototransposition reactions of methyl-substituted benzotrifluorides: Proof of the role of trifluoromethyl-substituted carbon
DeCosta, Dayal,Pincock, James
, p. 9484 - 9487 (2007/10/03)
Irradiation in acetonitrile of any one of the six isomers of dimethylbenzotrifluoride 8 resulted in efficient photoisomerization to the others. The dominant processes in these phototransposition reactions divides the isomers into two triads. The first consists of 8-2,6 (2,6-dimethylbenzotrifluoride), 8-2,3, and 8-3,4; the second consists of 8-3,5, 8-2,4, and 8-2,5. Moreover, irradiation of 2,6-dideuterio-4-methylbenzotrifluoride 5-d2 resulted in formation of 5,6-dideuterio-3-methylbenzotrifluoride 6-d2. These observations demonstrate that it is the trifluoromethyl-substituted carbon that is the migratory one in these reactions.
Process for the introduction of fluoro substituents
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, (2008/06/13)
A one pot process for the perfluoroalkylation and/or perfluoroacyloxylation of organic substrates is provided. The process comprises contacting a substrate with a perfluoroalkanoic anhydride in the presence of an inorganic peroxygen compound at a temperature of greater than 10° C. Substrates that can be perfluoroalkylated and/or perfluoroacyloxylated include alkylbenzenes, halogenated aromatic compounds, alkoxybenzenes, aryl benzenes, and aromatic and aliphatic disulphides. Preferably, the perfluoroalkanoic anhydride is trifluoroacetic anhydride and the inorganic peroxygen compound is sodium percarbonate.
Process for perfluoroalkylation of aromatic derivatives
-
, (2008/06/13)
A process for the perfluoroalkylation of aromatic derivatives. In a first stage, an aromatic derivative, sulfur dioxide and a metal selected from the group consisting of zinc, aluminum, manganese, cadmium, magnesium, tin, iron, nickel and cobalt, are brought into contact in a solvent, preferably a polar aprotic solvent. In a second stage, a perfluoroalkyl bromide or iodide is added to react with the aromatic derivative.
