Abstract
The inclusion complexation of new methylene blue (NMB) with cucurbit[7]uril (CB[7]) was studied spectrophotometrically. It was found that CB[7] forms a 1:1 inclusion complex with NMB in alcohol-water mixtures and the structure of the inclusion complex has been established by 1H-NMR measurements. We have determined the association constants of CB[7] with NMB under high pressures. The association constants of CB[7] increase as the external pressure and solvent polarity increase. Pressure dependence experiments enabled us to calculate the reaction volume for inclusion of CB[7] to range from -15.8 to -10.8 cm3 mol-1. From analyses of the high-pressure results, the volume change caused by water and/or alcohol molecules repelled from the CB[7] cavity in the alcohol-water mixtures was evaluated, which is indicative of the presence of water and/or alcohol molecules in the CB[7] cavity in the alcohol-water mixtures. The volume of molecules repelled from the CB[7] cavity plays an important role in the volume change upon inclusion.
Original language | English |
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Pages (from-to) | 153-161 |
Number of pages | 9 |
Journal | Zeitschrift fur Physikalische Chemie |
Volume | 222 |
Issue number | 1 |
DOIs | |
Publication status | Published - Feb 1 2008 |
Keywords
- Cucurbit[7]uril
- Inclusion complexation
- Pressure effect
- Solvent effect
ASJC Scopus subject areas
- Physical and Theoretical Chemistry