caa a22 4500 378932349 CHVBK 20180305123632.0 cr unu---uuuuu 161128e20041001xx s 000 0 eng 10.1524/zpch.218.10.1187.43590 doi (NATIONALLICENCE)gruyter-10.1524/zpch.218.10.1187.43590 Electron Spin Resonance Studies of Kinetic Effects of Substituent and Crown Ether on Intramolecular Sodium Cation Exchange in 2,5-Di-Tert-Amyl- and 2,5-Di-Tert-Butyl-1,4-Benzoquinone Radical Anions [Elektronische Daten] [Yoshimi Sueishi, Masamichi Kasahara, Kayo Okawa, Shunzo Yamamoto] Upon an addition of crown ethers to a solution of 2,5-di-tert-amyl-1,4-benzoquinone (2,5-DAQ) and 2,5-di-tert-butyl-1,4-benzoquinone (2,5-DBQ) radical anions, the significant broadening of the two-center lines was observed in their electron spin resonance (ESR) spectra. The formation constants for the complexation of sodium cation with three kinds of crown ethers in 2,5-DAQ and 2,5-DBQ radical ion pairs were estimated, and the intramolecular two-site jumping rates of sodium cation complexed with crown ethers were determined. Differential effects of steric and crown ether were found in the intramolecular sodium cation migration. The stabilization of inclusion complex of sodium cation with crown ethers gives rise to the acceleration effects on the rates of intramolecular migration of cation/crown-ether complex. Based on the results, a kinetic explanation for the intramolecular sodium cation migration in the presence of crown ethers was given. © 2004 Oldenbourg Wissenschaftsverlag GmbH Thermodynamics & statistical physics nationallicence Laboratory techniques, experiments nationallicence Physical chemistry nationallicence Sueishi Yoshimi aut Kasahara Masamichi aut Okawa Kayo aut Yamamoto Shunzo aut Zeitschrift für Physikalische Chemie/International journal of research in physical chemistry and chemical physics Oldenbourg Wissenschaftsverlag GmbH 218/10/2004(2004-10-01), 1187-1196 0942-9352 218:10/2004<1187 2004 218 zpch https://doi.org/10.1524/zpch.218.10.1187.43590 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.1524/zpch.218.10.1187.43590 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sueishi Yoshimi aut NATIONALLICENCE 700 1- Kasahara Masamichi aut NATIONALLICENCE 700 1- Okawa Kayo aut NATIONALLICENCE 700 1- Yamamoto Shunzo aut NATIONALLICENCE 773 0- Zeitschrift für Physikalische Chemie/International journal of research in physical chemistry and chemical physics Oldenbourg Wissenschaftsverlag GmbH 218/10/2004(2004-10-01), 1187-1196 0942-9352 218:10/2004<1187 2004 218 zpch CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter