1409976-23-3Relevant academic research and scientific papers
Trifluoromethylthiolation, Trifluoromethylation, and Arylation Reactions of Difluoro Enol Silyl Ethers
Jiang, Xingguo,Meyer, Denise,Baran, Dominik,Cortés González, Miguel A.,Szabó, Kálmán J.
, p. 8311 - 8319 (2020/07/16)
This study reports a new application area of difluoro enol silyl ethers, which can be easily obtained from trifluoromethyl ketones. The main focus has been directed to the electrophilic fluoroalkylation and arylation methods. The trifluoromethylthiolation of difluoro enol silyl ethers can be used for the construction of a novel trifluoromethylthio-α,α-difluoroketone (-COCF2SCF3) functionality. The -CF2SCF3 moiety has interesting properties due to the electron-withdrawing, albeit lipophilic, character of the SCF3 group, which can be combined with the high electrophilicity of the difluoroketone motif. The methodology could also be extended to difluoro homologation of the trifluoromethyl ketones using the Togni reagent. In addition, we presented a method for transition-metal-free arylation of difluoro enol silyl ethers based on hypervalent iodines.
Development and Mechanistic Investigations of a Base-Free Suzuki-Miyaura Cross-Coupling of α,α-Difluoroacetamides via C-N Bond Cleavage
Amgoune, Abderrahmane,Bouyssi, Didier,Jeanneau, Erwann,Krachko, Tetiana,Monteiro, Nuno,Onida, Killian,Reina, Antonio
, p. 2189 - 2197 (2020/02/28)
This study describes the development and understanding of a palladium-catalyzed cross-coupling of fluoroacetamides with boronic acids, under base-free conditions, to selectively give valuable α,α-difluoroketone derivatives. Detailed mechanistic studies were conducted to assess the feasibility of each elementary step, that is, C(acyl)-N bond oxidative addition, followed by base-free transmetallation and reductive elimination. These investigations allowed the structural characterization of palladium(II)fluoroacyl intermediates derived from C-N bond oxidative addition of an amide electrophile. They also revealed the high reactivity of these intermediates for transmetallation with boronic acids without exogenous base. The mechanistic studies also provided a platform to design a practical catalytic protocol for the synthesis of a diversity of α,α-difluoroketones, including CF2H-ketones. Finally, the synthetic potential of this fluoroacylation methodology is highlighted in sequential, orthogonal C-Br and C-N bond functionalization of an α-bromo-α,α-difluoroacetamide with a focus on compounds of potential biological relevance.
METAL-CATALYZED COUPLING OF ARYL AND VINYL HALIDES WITH ALPHA, ALPHA-DIFLUOROCARBONYL COMPOUNDS
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Paragraph 00111, (2014/10/18)
The coupling of aryl, heteroaryl, and vinyl halides with α,α-difluoroketones or silyl ethers or siylenol ethers of α,α-difluoroketones and α,α-difluoroamides and esters are described. Further derivatization of the coupling products (such as ketone cleavage and Baeyer-Villiger oxidation) is also described.
Palladium catalyzed direct α-arylation of α,α- difluoroketones with aryl bromides
Guo, Chen,Wang, Ruo-Wen,Qing, Feng-Ling
, p. 135 - 142,8 (2020/08/20)
The palladium-catalyzed direct α-arylations of α,α- difluoroketones with diverse aryl bromides have been developed by using rac-BINAP as ligand and Cs2CO3 as a mild base in xylene. This method provides an efficient and straightforward access to a variety of α-aryl-α,α-difluoroketones with broad substrate scope.
