136483-17-5Relevant articles and documents
Modular Route to Azaindanes
Huang, Qi,Zard, Samir Z.
supporting information, p. 3895 - 3898 (2017/07/26)
A convergent radical based route to azaindanes is described, relying on the degenerative addition transfer of various substituted S-(pyridylmethyl)-O-ethyl dithiocarbonates (xanthates) to functional alkenes followed by radical cyclization onto the pyridine ring activated by protonation with trifluoroacetic acid. In one case, a richly decorated cyclohepta[b]pyridine could be assembled swiftly by allowing the first adduct to N-phenylmaleimide to undergo addition to N-allylphthalimide prior to cyclization.
Copper-mediated perfluoroalkylation of heteroaryl bromides with (phen)CuRF
Mormino, Michael G.,Fier, Patrick S.,Hartwig, John F.
supporting information, p. 1744 - 1747 (2014/04/17)
The attachment of perfluoroalkyl groups onto organic compounds has been a major synthetic goal over the past several decades. Previously, our group reported phenanthroline-ligated perfluoroalkyl copper reagents, (phen)CuR F, which react with aryl iodides and aryl boronates to form the corresponding benzotrifluorides. Herein the perfluoroalkylation of a series of heteroaryl bromides with (phen)CuCF3 and (phen)CuCF 2CF3 is reported. The mild reaction conditions allow the process to tolerate many common functional groups. Perfluoroethylation with (phen)CuCF2CF3 occurs in somewhat higher yields than trifluoromethylation with (phen)CuCF3, creating a method to generate fluoroalkyl heteroarenes that are less accessible from trifluoroacetic acid derivatives.
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.
Synthesis of trifluoromethylated azines via nucleophilic oxidative substitution of hydrogen by trifluoromethyl carbanions
Loska, Rafal,Majcher, Monika,Makosza, Mieczyslaw
, p. 5574 - 5580 (2008/02/09)
(Chemical Equation Presented) A novel, three-step method of trifluoromethylation of azines via oxidative nucleophilic substitution of hydrogen in the heteroaromatic ring by a CF3- carbanion is presented. The key reaction of this proc
The direct metalation and subsequent functionalization of trifluoromethyl-substituted pyridines and quinolines
Schlosser, Manfred,Marull, Marc
, p. 1569 - 1575 (2007/10/03)
Depending on the choice of the reagent, 2-(trifluoromethyl)-pyridine can be selectively metalated and subsequently carboxylated of otherwise functionalized either at the 3- or at the 6-position. "Optional site selectivity" can also be achieved with 4-(trifluoromethyl)pyridine, which may be deprotonated either at the 2- or at the 3-position. In contrast, 3-(trifluoromethyl)pyridine undergoes nucleophilic addition and ensuing decomposition whatever the base. Depending on the reaction conditions, 2-(trifluoromethyl)quinoline displays reactivity toward lithium reagents at its 3-, 4-, or 8-positions, 3-(trifluoromethyl)quinolines at the 2- or 4-positions, and 4-(trifluoromethyl)quinoline at the 2- or 3-positions. It was therefore possible to prepare four trifluoromethyl-substituted pyridinecarboxylic acids (1, 4, 9, and 10) and six trifluoromethyl-substituted quinolinecarboxylic acids (11, 13, 14, 15, 17, and 18) regioisomerically uncontaminated and in a most straightforward way. ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003).
