R. Manoharan, S. Dogra
Nov 1, 1989
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0
Influential Citations
4
Citations
Journal
Journal of Photochemistry and Photobiology A-chemistry
Abstract
Abstract The spectral characteristics of 2-fluorenaldehyde, 2-acetylfluorene and 2-benzoylfluorene have been studied in different solvents and at various acid concentrations. This study has shown that nπ* may be the lowest energy transition in non-polar and aprotic solvents but that ππ* is the lowest energy transition in water. The carbonyl group attains more planarity with respect to the fluorene moiety on excitation. The prototropic equilibrium follows the benzophenone acidity scale rather than Hammett's acidity scale. A medium effect is also observed during the protonation of the species. Contrary to literature reports at H0 − 8 the dication species are formed by protonating the carbonyl group and the fluorene ring at position 7.