Neutral species from "non-protic" N-heterocyclic ionic liquids

Oldamur Hollóczki, L. Nyulászi

Research output: Contribution to journalArticle

37 Citations (Scopus)

Abstract

Possible isomerisation of 1,2,3-trialkylimidazolium and 1-alkylpyridinium ion pairs by proton transfer and by the nucleophilic addition of the anion to the cation have been investigated at the B3LYP/6-31+G* and B3LYP/6-311+G** levels of density functional theory. The deprotonation energies of 1,2,3-trialkylimidazolium and 1-alkylpyridinium cations to diaza-pentafulvene and pyridinium-ylide, respectively, were only slightly larger than that of 1,3-dialkylimidazolium salts yielding N-heterocyclic carbenes. Accordingly, in the case of 1,2,3-dialkylimidazolium salt ion pairs the stability of the H-bonded complex between the fulvene and the corresponding acid can be comparable to that of the ion pair in the presence of sufficiently basic anions, such as acetate. In the case of the pyridinium salts the nucleophilicity of the cation dominates over the acidity, and the formation of 1,2- or 1,4-dihydropyridine derivatives is preferred over proton transfer.

Original languageEnglish
Pages (from-to)2634-2640
Number of pages7
JournalOrganic and Biomolecular Chemistry
Volume9
Issue number8
DOIs
Publication statusPublished - Apr 21 2011

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Ionic Liquids
Cations
Proton transfer
Salts
Ions
salts
cations
Anions
Protons
liquids
anions
Deprotonation
ions
protons
carbenes
Isomerization
Acidity
acidity
isomerization
Density functional theory

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Organic Chemistry
  • Biochemistry

Cite this

Neutral species from "non-protic" N-heterocyclic ionic liquids. / Hollóczki, Oldamur; Nyulászi, L.

In: Organic and Biomolecular Chemistry, Vol. 9, No. 8, 21.04.2011, p. 2634-2640.

Research output: Contribution to journalArticle

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