The R3O+center dot center dot center dot H+ Hydrogen Bond: Toward a Tetracoordinate Oxadionium(2+) Ion

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Date

2012-01-11

Author

Stoyanov, Evgenii S.
Günbaş, Emrullah Görkem
HAFEZİ, Nema
MASCAL, Mark
Stoyanova, Irini V.
Tham, Fook S.
Reed, Christopher A.

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Oxatriquinanes are tricyclic oxonium ions which are known to possess remarkable solvolytic stability compared to simple alkyl oxonium salts. Their rigid, hemispherical structure presents an oxygen at the apex of three fused five-membered rings. While trivalent oxygen species like these have been well described in the literature, the ability of oxygen to enter into a fourth covalent bonding relationship has been visited in theory and suggested by the outcome of certain reactions conducted in superacidic media, but has never been established by the characterization of a stable, persistent R3OH2+ or R4O2+ ion. In this study, the nucleophilicity of the oxatriquinane oxygen was evaluated first by a series of protonation studies using the Bronsted superacid H(CHB11Cl11) both in the solid state and in liquid HCl solution. The interaction of the oxatriquinane oxygen with a bridging carbocation was also examined. A strong case could be made for the occurrence of hydrogen bonding between H(CHB11Cl11) and oxatriquinane using IR spectroscopy. Under the most forcing protonation conditions, the oxatriquinane ring is cleaved to give a bridged, dicationic, protonated tetrahydrofuran-carbenium ion.

Subject Keywords

Chemistry, Azatriquinane, Acid, Proton, Density, Dication, Ab-initio, Deuterium exchange, Molecular-structure, Tertiary oxonium salts

URI

https://hdl.handle.net/11511/43186

Journal

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY

DOI

https://doi.org/10.1021/ja209942s

Collections

Department of Chemistry, Article

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Citation Formats

E. S. Stoyanov et al., “The R3O+center dot center dot center dot H+ Hydrogen Bond: Toward a Tetracoordinate Oxadionium(2+) Ion,” JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, pp. 707–714, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/43186.