ORGN 479 |
| Supramolecular host compounds featuring imidazolium residues arranged in a geometry predisposed to selectively bind anion hosts have been actively pursued for colorimetric and fluorescent sensor applications. The current work reports the preparation of bis(imidazolium) host compounds built upon the versatile and readily-prepared m-terphenyl scaffold. By placing imidazolium units at appropriate distances, a host compound with impressive selectivity for iodide anions has been delineated. The binding event has been probed by UV-vis, fluorescence, X-ray structure determination, NMR, and calculations. The effect of subtle structure variation on the scaffold at positions remote from the actual binding site are able to influence the binding affinity and even switch the anion that is preferentially bound by the host molecule. Host molecules were designed to facilitate strong anion-pi system interactions, and chromophore-appended variations are being prepared to afford anion-responsive materials absorbing in the visible spectrum. |
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Physical Organic Chemistry, Metal-Mediated Reactions, Asymmetric Reactions and Syntheses
8:00 PM-10:00 PM, Tuesday, August 21, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Organic Chemistry |