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Ion-transfer reactions at the interface between fluorous solvent 1,1,1,2,3,4,4,5,5,5-decafluoropentane (DFP) and water (W) were investigated voltammetrically. Within the potential window at the DFP | W interface, various non-fluorinated ions, including tetraphenylarsonium and tetraphenylborate, and fluorinated ions, including fluorocomplex and perfluoro- n -alkanoate ions, gave reversible voltammetric waves for their ion transfer across the DFP | W interface. Based on the tetraphenylarsonium-tetraphenylborate assumption, the formal potentials of their ion transfer could be determined in terms of the Galvani potential difference. Also, formal potentials for the transfer of bis(perfluoroalkanesulfonyl)imide ions at the DFP | W interface were determined potentiometrically. The formal Gibbs energies for the transfer of ions from DFP to W, which would provide the criteria necessary for evaluating the fluorophilicity/hydrophilicity of ions were calculated from the formal potentials, and were compared with the transfer energies from 1,2-dichloroethane to W and those from the organic solvent to DFP, as quantitative scales of the ions' lipophilicity/hydrophilicity and fluorophilicity/lipophilicity. [ABSTRACT FROM AUTHOR]

We present the availability of a fluorous solvent, 1,1,1,2,3,4,4,5,5,5-decafluoropentane (C5F10), for the non-aqueous medium in liquid-liquid electrochemistry. The solvent is immiscible, and forms stable interface with water (W). The solvent dissolved a high concentration of a hydrophobic electrolyte, tetrabutylammonium bis(nona fluorobutanesulfonyl)imide (TBABNSI), and the TBABNSI (C5F10) solution gave a high conductivity. The TBABNSI (C5F10)| LiCl (W) interface gave a polarizable potential window. Within the potential window, tetramethylammonium ion gave a reversible voltammetric wave due to its transfer across the C5F10 | W interface. The potential window became wider by replacement of the supporting electrolytes in C5F10- and W-phases. The results indicate that various ion-transfer reactions at the C5F10 | W interface can be studied voltammetrically. [ABSTRACT FROM AUTHOR]