[Ar(Ar′)I][N(CF3)2], effect of fluorine substituents on aryl groups of iodonium cations and of coordinating bases on the fluoride transfer from the anion to the cation

• Published in: Journal of fluorine chemistry Vol. 138; pp. 24 - 27
• Main Authors: Hirschberg, Markus E., Wenda, André, Frohn, Hermann-Josef, Ignat’ev, Nikolai V.
• Format: Journal Article
• Language: English
• Published: LAUSANNE Elsevier B.V 01.06.2012; Elsevier
• Subjects: Anion metathesis; Bis(trifluoromethyl)imide anion; Chemistry; Chemistry, Inorganic & Nuclear; Chemistry, Organic; Fluoride affinity; Fluoride transfer; Fluoroaryliodonium salts; Physical Sciences; Science & Technology; Bis(trifluoromethyl)imide anion; Fluoride affinity; Fluoride transfer; Fluoroaryliodonium salts; Anion metathesis; SALTS
• ISSN: 0022-1139; 1873-3328
• DOI: 10.1016/j.jfluchem.2012.03.004

[Display omitted] ► Synthesis of [Ar(Ar′)I][N(CF3)2] salts in CH3CN by anion metathesis. ► [Ar(Ar′)I][N(CF3)2] salts are stabilized by the coordinating solvent CH3CN or a stronger N-base. ► Removal of the stabilizing N-base is accompanied by fluoride transfer from the anion to the cation. ► Ar(Ar′)IF is an efficient fluoride donor and forms [N(CF3)2]− when reacted with CF3SO2N(CF3)2. Three prototypical fluoroaryliodonium salts with the [N(CF3)2]− anion were obtained by metathesis in the corresponding tetrafluoroborate salts [Ar(Ar′)I][BF4] (Ar/Ar′=C6H5/4-FC6H4, 3-FC6H4/4-FC6H4, C6F5/C6F5) with in situ generated Rb[N(CF3)2]. The kinetic lability of the [N(CF3)2]− anion (potential fluoride donor like [OCF3]−) in combination with the gradual change in fluoride affinity of the three [Ar(Ar′)I]+ fluoroaryliodonium cations allowed to distinguish the fluoride acceptor property of the three [Ar(Ar′)I]+ fluoroaryliodonium cations. Coordinating solvents or ligands suppressed the fluoride transfer from the [N(CF3)2]− anion to the fluoroaryliodonium cation.