Triflidic acid
 | |
| Names | |
|---|---|
| Preferred IUPAC name [Bis(trifluoromethanesulfonyl)methanesulfonyl]tri(fluoro)methane | |
| Other names Triflidic acid, tris(triflyl)methane, tris[(trifluoromethyl)sulfonyl]methane | |
| Identifiers | |
3D model (JSmol) | |
| ChemSpider | |
| ECHA InfoCard | 100.258.613 |
PubChem CID | |
CompTox Dashboard (EPA) | |
| |
| |
| Properties | |
| C4HF9O6S3 | |
| Molar mass | 412.21 g·mol−1 |
| Appearance | Colorless solid |
| Melting point | 69.2 °C (156.6 °F; 342.3 K) |
| Miscible | |
| Acidity (pKa) | –18.6 (aqueous, est.)[1] |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards | Corrosive, eye irritant |
| GHS labelling: | |
  | |
| Danger | |
| H314, H335 | |
| P260, P261, P264, P271, P280, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P312, P321, P363, P403+P233, P405, P501 | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
Triflidic acid (IUPAC name: tris[(trifluoromethyl)sulfonyl]methane, abbreviated formula: Tf3CH) is an organic superacid. It is one of the strongest known carbon acids and is among the strongest Brønsted acids in general, with an acidity exceeded only by the carborane acids. Notably, triflidic acid is estimated to have an acidity 104 times that of triflic acid (pKaaq ~ –14), as measured by its acid dissociation constant. It was first prepared in 1987 by Seppelt and Turowsky by the following route:[2]
- (1) Tf2CH2 + 2 CH3MgBr → Tf2C(MgBr)2 + 2 CH4
- (2) Tf2C(MgBr)2 + TfF → Tf3C(MgBr) + MgBrF
- (3) Tf3C(MgBr) + H2SO4 → Tf3CH + MgBrHSO4
In its anionic form, the lanthanide salts of triflidic acid ("triflides") have been shown to be more efficient Lewis acids than the corresponding triflates.[3][4] The triflide anion has also been employed as the anionic component of ionic liquids.[5]
See also
[edit]References
[edit]- ^ Barrett, A. G. M.; Braddock, D. C.; Raju, G. S. (2004). "Tris[(trifluoromethyl)sulfonyl]methane and Related Salts". In Charette, André; Bode, Jeffrey; Rovis, Tomislav; Shenvi, Ryan (eds.). Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.rn00441. ISBN 9780470842898.
- ^ Turowsky, Lutz; Seppelt, Konrad (1988-06-01). "Tris[(trifluoromethyl)sulfonyl]methane, HC(SO2CF3)3". Inorganic Chemistry. 27 (12): 2135–2137. doi:10.1021/ic00285a025. ISSN 0020-1669.
- ^ Waller, Francis J.; Barrett, Anthony G. M.; Braddock, D. Christopher; Ramprasad, Dorai; McKinnell, R. Murray; White, Andrew J. P.; Williams, David J.; Ducray, Richard (1999-04-01). "Tris(trifluoromethanesulfonyl)methide ("Triflide") Anion: Convenient Preparation, X-ray Crystal Structures, and Exceptional Catalytic Activity as a Counterion with Ytterbium(III) and Scandium(III)". The Journal of Organic Chemistry. 64 (8): 2910–2913. doi:10.1021/jo9800917. ISSN 0022-3263. PMID 11674365.
- ^ Ishihara, Kazuaki; Hiraiwa, Yukihiro; Yamamoto, Hisashi (2000-01-01). "Homogeneous Debenzylation Using Extremely Active Catalysts: Tris(triflyl)methane, Scandium(III) Tris(triflyl)methide, and Copper(II) Tris(triflyl)methide". Synlett. 2000 (1): 80–82. doi:10.1055/s-2000-6436. ISSN 0936-5214. S2CID 196771067.
- ^ Johansson, Katarina M.; Adebahr, Josefina; Howlett, Patrick C.; Forsyth, Maria; MacFarlane, Douglas R. (2007-01-01). "N-Methyl-N-Alkylpyrrolidinium Bis(perfluoroethylsulfonyl)amide ([NPf2]) and Tris(trifluoromethanesulfonyl)methide ([CTf3]) Salts: Synthesis and Characterization". Australian Journal of Chemistry. 60 (1): 57–63. doi:10.1071/ch06299.