Control of the Ketone to Gem-diol Equilibrium by Host-guest Interactions
In water, N-methyl-4-(p-substituted benzoyl)pyridinium cations, BP-X, exist in equilibrium with their hydrated forms (gem-diols), whose concentrations depend on the para substituent (-X). In the presence of cucurbituril (CB), the benzoyl group shows a preference for the CB cavity, and the ketone to gem-diol equilibrium is shifted toward the keto form, meaning that the stabilization realized through hydrophobic interactions of the benzoyl group in the CB cavity exceeds the hydrogen-bonding stabilization of the gem-diols in the aqueous environment.
A. M. Rawashdeh et al., "Control of the Ketone to Gem-diol Equilibrium by Host-guest Interactions," Organic Letters, American Chemical Society (ACS), Jan 2007.
The definitive version is available at http://dx.doi.org/10.1021/ol800021r
University of Missouri Research Board
Article - Journal
© 2007 American Chemical Society (ACS), All rights reserved.