ORGN 345 |
| Adam J. Matzger, Xinnan Zhang, and James P. Johnson. Department of Chemistry and Macromolecular Science and Engineering, University of Michigan, 930 N. University, Ann Arbor, MI 48109-1055 |
| Oligothiophenes have received much attention due to their excellent electronic and optical properties. To determine the influence of planarization on the properties of these compounds, a series of fused-ring oligothiophenes were designed and synthesized in which two or more of the thiophene rings were replaced by thieno[3,2-b]thiophene and dithieno[3,2-b:2’,3’-d]thiophene rings. Their synthesis was achieved through a combination of cross coupling and oxidative coupling strategies with removable solublizing groups to facilitate purification. The electronic properties of these oligomers were studied by UV-visible absorbance and fluorescence spectroscopy. In solution, the introduction of sulfur linkages into oligothiophenes, with a constant number of double bonds, leads to a blue shift of maximum emission without changing the maximum absorption wavelength. In the solid-state, the absorption spectra of these oligomers change and these trends will be discussed. The crystal structures of several oligomers indicate that planar conformations are favored and that the molecules prefer to adopt herringbone packing patterns. |
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Materials, Devices, and Switches
1:00 PM-5:00 PM, Tuesday, August 24, 2004 Pennsylvania Convention Center -- 201B, Oral
Division of Organic Chemistry |