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Updated: Jun 21, 2025

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Fluorinated Dialkyl Chloronium Salts: Synthesis and Reactivity for Fluoroalkylation and Hydride Abstraction
Lukas Fischer1, Michael H Lee1, Isaac Kim1
1Fachbereich Biologie, Chemie, Pharmazie Institut für Chemie und Biochemie-Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34/36, 14195, Berlin, Germany.
Abstract:
A new concept for the synthesis of dialkyl chloronium cations [R-Cl-R]+ is described (R=CH3, CH2CF3), that allows the formation of fluorinated derivatives. By utilizing the xenonium salt [XeOTeF5][M(OTeF5)n] (M=Sb, n=6; M=Al, n=4) chlorine atoms of chloroalkanes or the deactivated chlorofluoroalkane CH2ClCF3 are oxidized and removed as ClOTeF5 leading to the isolation of the corresponding chloronium salt. Since the resulting highly electrophilic cation [Cl(CH2CF3)2]+ is able to alkylate weak nucleophiles, this compound can be utilized for the introduction of a fluorinated alkyl group to those. In addition, the fluorinated alkyl chloronium cation displays a high hydride ion affinity, enabling the activation of linear hydrocarbons by hydride abstraction even at low temperatures ultimately leading to the formation of branched carbocations.
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