Abstract
On the basis of the highly stable G 2H (2:1) ternary complex formed by two methyl viologen cation radicals inside the cavity of cucurbit[8]uril, we prepared three monocationic 4-phenylpyridinium derivatives: 1-(hydroxyethyl)-4-phenyl-pyridinium (1 +) bromide, 1-(octaethyleneglycol)-4-phenyl-pyridinium (2 +) chloride, and 4-[4-(methoxymethoxy)phenyl]pyridinium (3 +) iodide, as possible guests for 2:1 complexation inside cucurbit[8]uril. We also investigated a fourth monocationic guest (4 +), in which a central vinylidene group is inserted to elongate the 4-phenyl-pyridinium residue. Using 1H NMR and UV-Vis spectroscopic data and mass spectrometric data, we obtained unequivocal evidence for the formation of G 2H (2:1) ternary complexes in all cases. The stoichiometry of the complexes was further verified by continuous variation (Job) plots, and in some cases, high resolution ESI-MS spectrometric data. Diffusion coefficient measurements, using 1H NMR pulse gradient spin echo techniques, yielded values consistent with the formation and expected structures of the ternary complexes.
Original language | English (US) |
---|---|
Pages (from-to) | 592-596 |
Number of pages | 5 |
Journal | Journal of Physical Organic Chemistry |
Volume | 25 |
Issue number | 7 |
DOIs | |
State | Published - Jul 2012 |
Keywords
- cucurbituril hosts
- host-guest complexes
- inclusion complexes
- ternary complexes
ASJC Scopus subject areas
- Organic Chemistry
- Physical and Theoretical Chemistry