TY - JOUR
T1 - Reduction of 1,4-quinone and ubiquinones by hydrogen atom transfer under UVA irradiation
AU - Biondi, Cristiano
AU - Galeazzi, Roberta
AU - Littarru, Gianpaolo
AU - Greci, Lucedio
PY - 2002/4/1
Y1 - 2002/4/1
N2 - 1,4-Benzoquinone, coenzyme Q0 and Q10 were reacted with a series of hydrogen donors in the ESR cavity in the presence or absence of UVA irradiation. The signals of the radicals generated from the hydrogen donors or of those of the semiquinones were detected. The reaction mechanism was interpreted by a hydrogen atom transfer instead of the usual electron transfer mechanism on the basis of the redox potentials of the reactants and the Marcus theory. The hydrogen atom transfer is explained by the excited triplet state of quinones, which, on the basis of quantum mechanic calculations, may be reached even under visible light. In some cases, hydrogen atom transfer was also observed without irradiation, although to a lesser extent.
AB - 1,4-Benzoquinone, coenzyme Q0 and Q10 were reacted with a series of hydrogen donors in the ESR cavity in the presence or absence of UVA irradiation. The signals of the radicals generated from the hydrogen donors or of those of the semiquinones were detected. The reaction mechanism was interpreted by a hydrogen atom transfer instead of the usual electron transfer mechanism on the basis of the redox potentials of the reactants and the Marcus theory. The hydrogen atom transfer is explained by the excited triplet state of quinones, which, on the basis of quantum mechanic calculations, may be reached even under visible light. In some cases, hydrogen atom transfer was also observed without irradiation, although to a lesser extent.
KW - Hydrogen abstraction
KW - Marcus theory
KW - Redox potentials
KW - Ubiquinones
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U2 - 10.1080/10715760290021243
DO - 10.1080/10715760290021243
M3 - Article
C2 - 12069103
AN - SCOPUS:0036554588
VL - 36
SP - 399
EP - 404
JO - Free Radical Research
JF - Free Radical Research
SN - 1071-5762
IS - 4
ER -