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Landmann J, Sprenger JAP, Hennig PT, Bertermann R, Grüne M, Würthner F, Ignat'ev NV, Finze M. Perfluoroalkyltricyanoborate and Perfluoroalkylcyanofluoroborate Anions: Building Blocks for Low-Viscosity Ionic Liquids. Chemistry 2017; 24:608-623. [PMID: 28884848 DOI: 10.1002/chem.201703685] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Indexed: 12/24/2022]
Abstract
The potassium perfluoroalkyltricyanoborates K[Cn F2 n+1 B(CN)3 ] [n=1 (1 d), 2 (2 d)] and the potassium mono(perfluoroalkyl)cyanofluoroborates K[Cn F2 n+1 BF(CN)2 ] [n=1 (1 c), 2 (2 c)] and [Cn F2 n+1 BF2 (CN)]- [n=1 (1 b), 2 (2 b), 3 (3 b), 4 (4 b)] are accessible with perfect selectivities on multi-gram scales starting from K[Cn F2 n+1 BF3 ] and Me3 SiCN. The K+ salts are starting materials for the preparation of salts with organic cations, for example, [EMIm]+ (EMIm=1-ethyl-3-methylimidazolium). These [EMIm]+ salts are hydrophobic room-temperature ionic liquids (RTILs) that are thermally, chemically and electrochemically very robust, offering electrochemical windows up to 5.8 V. The RTILs described herein, exhibit very low viscosities with a minimum of 14.0 mPa s at 20 °C for [EMIm]1 c, low melting points down to -57 °C for [EMIm]2 b and extraordinary high conductivities up to 17.6 mS cm-1 at 20 °C for [EMIm]1 c. The combination of these properties makes these ILs promising materials for electrochemical devices as exemplified by the application of selected RTILs as component of electrolytes in dye-sensitised solar cells (DSSCs, Grätzel cells). The efficiency of the DSSCs was found to increase with a decreasing viscosity of the neat ionic liquid. In addition to the spectroscopic characterisation, single crystals of the potassium salts of the anions 1 b-d, 2 d, 3 b and 4 c as well as of [nBu4 N]2 c have been studied by X-ray diffraction.
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Affiliation(s)
- Johannes Landmann
- Julius-Maximilians-Universität Würzburg, Institut für Anorganische Chemie, Institut für nachhaltige Chemie & Katalyse mit Bor (ICB), Am Hubland, 97074, Würzburg, Germany
| | - Jan A P Sprenger
- Julius-Maximilians-Universität Würzburg, Institut für Anorganische Chemie, Institut für nachhaltige Chemie & Katalyse mit Bor (ICB), Am Hubland, 97074, Würzburg, Germany
| | - Philipp T Hennig
- Julius-Maximilians-Universität Würzburg, Institut für Anorganische Chemie, Institut für nachhaltige Chemie & Katalyse mit Bor (ICB), Am Hubland, 97074, Würzburg, Germany
| | - Rüdiger Bertermann
- Julius-Maximilians-Universität Würzburg, Institut für Anorganische Chemie, Institut für nachhaltige Chemie & Katalyse mit Bor (ICB), Am Hubland, 97074, Würzburg, Germany
| | - Matthias Grüne
- Julius-Maximilians-Universität Würzburg, Institut für Organische Chemie &, Center for Nanosystems Chemistry, Am Hubland, 97074, Würzburg, Germany
| | - Frank Würthner
- Julius-Maximilians-Universität Würzburg, Institut für Organische Chemie &, Center for Nanosystems Chemistry, Am Hubland, 97074, Würzburg, Germany
| | - Nikolai V Ignat'ev
- Julius-Maximilians-Universität Würzburg, Institut für Anorganische Chemie, Institut für nachhaltige Chemie & Katalyse mit Bor (ICB), Am Hubland, 97074, Würzburg, Germany.,Merck KGaA, Frankfurter Strasse 250, 64293, Darmstadt, Germany
| | - Maik Finze
- Julius-Maximilians-Universität Würzburg, Institut für Anorganische Chemie, Institut für nachhaltige Chemie & Katalyse mit Bor (ICB), Am Hubland, 97074, Würzburg, Germany
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Königsberger K, Chen GP, Vivelo J, Lee G, Fitt J, McKenna J, Jenson T, Prasad K, Repič O. An Expedient Synthesis of 6α-Fluoroursodeoxycholic Acid. Org Process Res Dev 2002. [DOI: 10.1021/op0255433] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Millet R, Meulon E, Goossens L, Houssin R, Hénichart JP, Rigo B. Conformationally constrained dipeptides. Obtention of enantiomerically pure 6-acetamido-5-oxo-1,2,3,5,6,7-hexahydro-3-indolizine carboxylic acid. J Heterocycl Chem 2000. [DOI: 10.1002/jhet.5570370613] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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