ORGN 321 |
| Jinhua Yang1, Amala Dass1, Chariklia Sotiriou-Leventis1, and Nicholas Leventis2. (1) Department of Chemistry, University of Missouri-Rolla, 142 Schrenk Hall, Rolla, MO 65409, (2) Polymer Branch / Materials Division, NASA Glenn Research Center, 2100 Brookpark Road MS 49-1, Cleveland, OH 44135 |
| A series of arylethynyl substituted anthraquinones were synthesized via Sonogashira coupling reactions of 2,7-dibromo-, 2,6-dibromo- and 2-bromoanthraquinone with para-substituted phenylacetylenes. While the redox properties of those compounds are almost insensitive to substitution, their absorption maxima are linearly related to the Hammett constants for electron donating and electron withdrawing groups separately. All compounds are photoluminescent both in solution (quantum yield of emission ~ 2%) and as solids. X-ray crystallographic characterization of 2,7-bisphenylethynyl anthraquinone indicates a monoclinic p2(1/n) space group and no indication for pi-overlap that would promote self-quenching. The emission maxima are red-shifted by both electron donating and electron withdrawing groups alike. The Stokes shifts of all compounds are significant and are correlated to the electronic properties of the substituents. The reduced forms of these compounds are also photoluminescent and the emission originates from the dihydroanthraquinone core. |
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Physical Organic, Combinatorial, Materials, Molecular Recognition
8:00 PM-10:00 PM, Tuesday, March 30, 2004 Anaheim Convention Center -- Hall A, Poster
Division of Organic Chemistry |