G. Wiosna, I. Petkova, M. S. Mudadu
Dec 21, 2004
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0
Influential Citations
34
Citations
Journal
Chemical Physics Letters
Abstract
Abstract Three isomeric 7-(pyridyl)indoles reveal very different, solvent-dependent photophysical properties. Due to rapid excited state depopulation involving intramolecular hydrogen bonding, 7-(2′-pyridyl)indole is practically nonfluorescent at room temperature. In nonpolar and polar aprotic solvents, 7-(3′-pyridyl)indole and 7-(4′-pyridyl)indole fluorescence strongly, but the emission is quenched in alcohols. Syn and anti rotameric forms of 7-(3′-pyridyl)indole are detected, each quenched to a different degree. This differential quenching is interpreted as evidence of enhanced S 1 → S 0 internal conversion being more efficient in cyclic solvates, with alcohol molecules forming a bridge between the proton donor and acceptor groups of an excited chromophore.