A Zwitterionic, 10 π Aromatic Hemisphere

Nema Hafezi, Wondimagegn T. Shewa, James C. Fettinger, Mark Mascal

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

A new concept in anionic 10 π aromaticity is described by the embedding of a compensating charge within an aromatic cyclononatetraenide ring by the symmetric superposition of an alkyl ammonium bridge. This is accomplished by the methylation of azatriquinacene to give a quaternary ammonium salt, followed by oxidation to the tetraene and final deprotonation. The resulting zwitterion is a stable [9]annulene with strong aromaticity as shown by its degree of C−C bond equalization and a nucleus-independent chemical shift value lower than that of benzene. The solid-state structure shows an eclipsed stacking motif with the electron-poor ammonium methyl groups occupying the electron-rich cavity of the aromatic bowl.

Original languageEnglish (US)
Pages (from-to)14141-14144
Number of pages4
JournalAngewandte Chemie - International Edition
Volume56
Issue number45
DOIs
StatePublished - Nov 6 2017

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Ammonium Compounds
Deprotonation
Methylation
Electrons
Chemical shift
Benzene
Salts
Oxidation

Keywords

  • ab initio calculations
  • annulenes
  • aromaticity
  • hemispherical molecules
  • zwitterions

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)

Cite this

Hafezi, N., Shewa, W. T., Fettinger, J. C., & Mascal, M. (2017). A Zwitterionic, 10 π Aromatic Hemisphere. Angewandte Chemie - International Edition, 56(45), 14141-14144. https://doi.org/10.1002/anie.201708521

A Zwitterionic, 10 π Aromatic Hemisphere. / Hafezi, Nema; Shewa, Wondimagegn T.; Fettinger, James C.; Mascal, Mark.

In: Angewandte Chemie - International Edition, Vol. 56, No. 45, 06.11.2017, p. 14141-14144.

Research output: Contribution to journalArticle

Hafezi, N, Shewa, WT, Fettinger, JC & Mascal, M 2017, 'A Zwitterionic, 10 π Aromatic Hemisphere', Angewandte Chemie - International Edition, vol. 56, no. 45, pp. 14141-14144. https://doi.org/10.1002/anie.201708521
Hafezi, Nema ; Shewa, Wondimagegn T. ; Fettinger, James C. ; Mascal, Mark. / A Zwitterionic, 10 π Aromatic Hemisphere. In: Angewandte Chemie - International Edition. 2017 ; Vol. 56, No. 45. pp. 14141-14144.
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