Two macrocyclic squares (one with four Pd 21 corners, the other with four Pte+ corners) were synthesized according to literature methods."2 The charge-transfer complexes which formed when each were mixed with a bis(thiol)hydroquinone were then studied by UV-VIS, NMR, and IR spectroscopy. The UV-VIS data obtained indicated a stoichiometric relationship of I mole of molecular square to 2 moles of dithiol and a very large binding constant. Further evidence for the association between each macrocyclic square and the dithiol was observed in the NMR spectrum by the shifting of the proton resonances on the bipyridine unit of the molecular square and in the IR spectra by the changes in the aromatic ring absorptions of the dithiol and the bipyridine ring absorptions of the square.A monolayer formed on gold from a dilute solution of the dithiol in ethanol and a monolayer formed from a dilute solution of a 6:1 ratio of molecular square to dithiol were each observed by infrared grazing angle spectroscopy. The spectrum of the dithiol monolayer indicated that the aromatic ring was oriented perpendicular to the gold surface. The infrared spectrum of the square/dithiol monolayer showed the presence of triflate absorptions and methyl stretches, suggesting the square was attached via a catanane formation. Furthermore, the spectral data indicated that upon formation of the catanane, the aromatic ring of the dithiol and the bipyridine rings of the square were oriented parallel to the gold surface. / Department of Chemistry
| Identifer | oai:union.ndltd.org:BSU/oai:cardinalscholar.bsu.edu:handle/186754 |
| Date | January 2000 |
| Creators | Tran, Khoa V. |
| Contributors | Lang, Patricia L. |
| Source Sets | Ball State University |
| Detected Language | English |
| Format | ix, 110 leaves : ill. (some col.) ; 28 cm. |
| Source | Virtual Press |
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