caa a22 4500 475759141 CHVBK 20180406123545.0 cr unu---uuuuu 170329e20000901xx s 000 0 eng 10.1007/BF02495150 doi (NATIONALLICENCE)springer-10.1007/BF02495150 Photoreduction of ortho -benzoquinones in the presence of para -substituted N,N -dimethylanilines [Elektronische Daten] [S. Chesnokov, V. Cherkasov, Yu. Chechet, N. Nevodchikov, G. Abakumov, O. Mamysheva] Photoreduction ofo-benzoquinones irradiated at the wavelengths λmax ≈ 400 and 600 nm corresponding to the S(π → π*) and S(n → π*) electron transitions in the >C=0 groups, respectively, in the presence ofN,N-dimethylaniline and its derivatives was studied. The apparent rate constants of the photoreduction (k H) ofo-quinones are determined by the free energy of electron transfer from the amine molecule to a photoexcitedo-quinone molecule (ΔG e.t). The ΔG e.t. values are calculated as the sums of the energies of the 0→0 transitions of the lowest triplet excited state ofo-quinones, the reduction energies ofo-quinones, and the oxidation energies of amines (the last two terms are numerically equal to the corresponding redox potentials). The maximum rate of photoreduction was found for ΔG e.t≈0. The reaction mechanism is proposed, in which the reversible formation of a triplet exiplex is the rate-determining stage and hydrogen transfer proceeds in parallel with electron transfer within the exiplex. Kluwer Academic/Plenum Publishers, 2000 ortho -quinones nationallicence N,N -dimethylanilines nationallicence photoreduction nationallicence free energy of electron transfer nationallicence Chesnokov S. G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut Cherkasov V. G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut Chechet Yu G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut Nevodchikov N. G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut Abakumov G. G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut Mamysheva O. G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut Russian Chemical Bulletin Kluwer Academic Publishers-Plenum Publishers 49/9(2000-09-01), 1506-1511 1066-5285 49:9<1506 2000 49 11172 https://doi.org/10.1007/BF02495150 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02495150 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Chesnokov S. G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut NATIONALLICENCE 700 1- Cherkasov V. G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut NATIONALLICENCE 700 1- Chechet Yu G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut NATIONALLICENCE 700 1- Nevodchikov N. G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut NATIONALLICENCE 700 1- Abakumov G. G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut NATIONALLICENCE 700 1- Mamysheva O. G. A. Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences, 49 ul. Tropinina, 603600, Nizhnii Novgorod, Russian Federation aut NATIONALLICENCE 773 0- Russian Chemical Bulletin Kluwer Academic Publishers-Plenum Publishers 49/9(2000-09-01), 1506-1511 1066-5285 49:9<1506 2000 49 11172 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer