Photophysical and Photochemical Properties of 2,3–Dihydro-4 (l H)-quinolinones. Part II. Rates and Mechanism of Primary Processes

Sn Bakalova, L. Biczók, T. Bérces

Research output: Article

1 Citation (Scopus)

Abstract

Fluorescence quantum yields, singlet lifetimes and triplet yields for 2–methyl-2,3–dihydro-4(1 H)-quinolinone and N-methyl-2,3–dihydro-4(l H)-quinolinone were determined as a function of temperature. In non-polar solvents, an efficient non-radiative process identified as an indirect singlet –> triplet transition occurring through S2(n,π*) was found to depopulate the lowest S,(,π*π) state. In polar solvents, direct singlet –» triplet intersystem crossing appears to dominate. Photochemical dehydrogenation produced the corresponding 4(1 H)-quinolinone with a yield of few times 10–2. This was shown to be the only traceable reaction route.

Original languageEnglish
Pages (from-to)549-556
Number of pages8
JournalZeitschrift fur Naturforschung - Section C Journal of Biosciences
Volume46
Issue number7-8
DOIs
Publication statusPublished - 1991

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Quinolones
Quantum yield
Dehydrogenation
Fluorescence
Temperature

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

Cite this

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title = "Photophysical and Photochemical Properties of 2,3–Dihydro-4 (l H)-quinolinones. Part II. Rates and Mechanism of Primary Processes",
abstract = "Fluorescence quantum yields, singlet lifetimes and triplet yields for 2–methyl-2,3–dihydro-4(1 H)-quinolinone and N-methyl-2,3–dihydro-4(l H)-quinolinone were determined as a function of temperature. In non-polar solvents, an efficient non-radiative process identified as an indirect singlet –> triplet transition occurring through S2(n,π*) was found to depopulate the lowest S,(,π*π) state. In polar solvents, direct singlet –» triplet intersystem crossing appears to dominate. Photochemical dehydrogenation produced the corresponding 4(1 H)-quinolinone with a yield of few times 10–2. This was shown to be the only traceable reaction route.",
keywords = "Dihydroquinolinones, Fluorescence Quantum Yields, Photochemical Dehydrogenation, Singlet Lifetimes, Triplet Yields",
author = "Sn Bakalova and L. Bicz{\'o}k and T. B{\'e}rces",
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language = "English",
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issn = "0939-5075",
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TY - JOUR

T1 - Photophysical and Photochemical Properties of 2,3–Dihydro-4 (l H)-quinolinones. Part II. Rates and Mechanism of Primary Processes

AU - Bakalova, Sn

AU - Biczók, L.

AU - Bérces, T.

PY - 1991

Y1 - 1991

N2 - Fluorescence quantum yields, singlet lifetimes and triplet yields for 2–methyl-2,3–dihydro-4(1 H)-quinolinone and N-methyl-2,3–dihydro-4(l H)-quinolinone were determined as a function of temperature. In non-polar solvents, an efficient non-radiative process identified as an indirect singlet –> triplet transition occurring through S2(n,π*) was found to depopulate the lowest S,(,π*π) state. In polar solvents, direct singlet –» triplet intersystem crossing appears to dominate. Photochemical dehydrogenation produced the corresponding 4(1 H)-quinolinone with a yield of few times 10–2. This was shown to be the only traceable reaction route.

AB - Fluorescence quantum yields, singlet lifetimes and triplet yields for 2–methyl-2,3–dihydro-4(1 H)-quinolinone and N-methyl-2,3–dihydro-4(l H)-quinolinone were determined as a function of temperature. In non-polar solvents, an efficient non-radiative process identified as an indirect singlet –> triplet transition occurring through S2(n,π*) was found to depopulate the lowest S,(,π*π) state. In polar solvents, direct singlet –» triplet intersystem crossing appears to dominate. Photochemical dehydrogenation produced the corresponding 4(1 H)-quinolinone with a yield of few times 10–2. This was shown to be the only traceable reaction route.

KW - Dihydroquinolinones

KW - Fluorescence Quantum Yields

KW - Photochemical Dehydrogenation

KW - Singlet Lifetimes

KW - Triplet Yields

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JO - Zeitschrift fur Naturforschung. Section C: Biosciences

JF - Zeitschrift fur Naturforschung. Section C: Biosciences

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