Infrared and electronic spectra of radicals produced from 2-naphthol and carbazole by UV-induced hydrogen-atom eliminations.
The photoreaction mechanisms of 2-naphthol and carbazole in low-temperature argon matrices have been investigated by infrared and electronic absorption spectroscopy with aids of density-functional-theory (DFT) and time-dependent DFT (TD-DFT) calculations. When the matrix samples were irradiated upon UV light, 2-naphthoxyl and N-carbazolyl radicals were produced by the elimination of the H atom in the O-H group of 2-naphthol and in the N-H group of carbazole, respectively. The observed IR and electronic absorption spectra of the radicals were reproduced satisfactorily by the quantum chemical calculations. To understand a role of the radicals in the excited-state proton transfer (ESPT), the fluorescence and excitation spectra of 2-naphthol and carbazole were measured in aqueous solution at room temperature as well as in the low-temperature argon matrices. It was found that the intensity of the fluorescence emitted from carbazole anion in aqueous solution decreased when oxygen gas was blown into the solution.
Graduate School of BASE (Bio-Applications and Systems Engineering), Tokyo University of Agriculture and Technology , Naka-cho, Koganei, Tokyo 184-8588, Japan.
Masahiko
M
Sekine
Hiroshi
H
Sekiya
Munetaka
M
Nakata
D002227:Carbazoles / Q000737:chemistry*; D003080:Cold Temperature; D005609:Free Radicals / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry*; D009284:Naphthols / Q000737:chemistry*; D010777:Photochemistry; D013055:Spectrophotometry, Infrared
D002227:Carbazoles; D005609:Free Radicals; D009284:Naphthols; C041514:carbazole; D006859:Hydrogen; C028405:2-naphthol