Abstract Organic fluoronium ions can be described as positively charged molecules in which the most electronegative and least polarizable element fluorine engages in two partially covalent bonding interactions to two carbon centers. While recent solvolysis experiments and NMR spectroscopic studies on a metastable [C–F–C]+fluoronium ion strongly support the divalent fluoronium structure over the alternative rapidly equilibrating classical carbocation, the model system has, to date, eluded crystallographic analysis to confirm this phenomenon in the solid state. Herein, we report the single crystal structure of a symmetrical [C–F–C]+fluoronium cation. Besides its synthesis and crystallographic characterization as the [Sb2F11]−salt, vibrational spectra are discussed and a detailed analysis concerning the nature of the bonding situation in this fluoronium ion and its heavier halonium homologues is performed, which provides detailed insights on this molecular structure.
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Ruthenium-Catalyzed C–F Bond Arylation of Polyfluoroarenes: Polyfluorinated Biaryls by Integrated C–F/C–H Functionalization
- Award ID(s):
- 1650766
- PAR ID:
- 10412445
- Date Published:
- Journal Name:
- ACS Catalysis
- Volume:
- 12
- Issue:
- 22
- ISSN:
- 2155-5435
- Page Range / eLocation ID:
- 14337 to 14346
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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