Transfer of cationic cucurbit[7]uril inclusion complexes from water to non-aqueous solvents

Wei Wang, Angel Kaifer

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

The redox-active guests (ferrocenylmethyl)trimethylammonium (2+) and methylviologen (52+) form stable complexes with the cucurbit[7]uril host (CB7) in aqueous solution. In this work, we report a method to transfer these cationic inclusion complexes - as their hexafluorophosphate salts - to less polar, non-aqueous solvents, such as CH3CN, dimethylformamide and dimethylsulphoxide (DMSO). Both inclusion complexes were found to be stable in these solvents, although the determination of accurate equilibrium association constants was hampered by the low solubility of the free host. Voltammetric experiments show that the one-electron oxidation of the ferrocenyl residue in the CB72+ complex increases its stability in CH3CN and DMSO solutions, while the opposite effect was observed in aqueous media. These results provide valuable insight into the various roles played by hydrophobic interactions, solvation effects and ion-dipole interactions at stabilising CB7 inclusion complexes of cationic guests.

Original languageEnglish
Pages (from-to)710-716
Number of pages7
JournalSupramolecular Chemistry
Volume22
Issue number11-12
DOIs
StatePublished - Nov 1 2010

Fingerprint

Dimethyl Sulfoxide
Water
Dimethylformamide
Solvation
Solubility
Salts
Association reactions
Ions
Oxidation
Electrons
cucurbit(7)uril
Experiments
(ferrocenylmethyl)trimethylammonium
Oxidation-Reduction

Keywords

  • cucurbiturils
  • electrochemistry
  • host-guest complexes
  • non-aqueous solvents

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Transfer of cationic cucurbit[7]uril inclusion complexes from water to non-aqueous solvents. / Wang, Wei; Kaifer, Angel.

In: Supramolecular Chemistry, Vol. 22, No. 11-12, 01.11.2010, p. 710-716.

Research output: Contribution to journalArticle

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