TY - JOUR
T1 - Persistent C60 anion-radical formation via photoinduced electron transfer from tetraphenylborate and triphenylbutylborate
AU - Konishi, Toshifumi
AU - Sasaki, Yoshiko
AU - Fujitsuka, Mamoru
AU - Toba, Yasumasa
AU - Moriyama, Hiroshi
AU - Ito, Osamu
PY - 1999/3
Y1 - 1999/3
N2 - Photochemical reactions between photo-excited C60 and borates (-BPh4 and -BPh3Bu) have been investigated by steady-state photolysis and laser flash photolysis. On steady-state photolysis of C60 in the presence of the borates in polar solvents, the absorption OfC60-• increases with irradiation time, suggesting that irreversible photoinduced electron-transfer occurs. By the measurements of the transient absorption spectra, it is indicated that electron transfer takes place from the borate anions to 3C60*, yielding C60-• and •BPh3R (R = Ph or Bu), in which the latter dissociates into Ph3B and R•, yielding biphenyl (or octane). Electron-donor ability of -BPh3 Bu is higher than that of -BPh4, while the steady-state photolysis to a C60/borate system shows an opposite tendency. The addition reaction of C60-• with Bu• yielding BuC60- is more efficient than that with Ph• producing PhC60-. The rate constant of electron-transfer via the triplet state of C60 increases with solvent polarity.
AB - Photochemical reactions between photo-excited C60 and borates (-BPh4 and -BPh3Bu) have been investigated by steady-state photolysis and laser flash photolysis. On steady-state photolysis of C60 in the presence of the borates in polar solvents, the absorption OfC60-• increases with irradiation time, suggesting that irreversible photoinduced electron-transfer occurs. By the measurements of the transient absorption spectra, it is indicated that electron transfer takes place from the borate anions to 3C60*, yielding C60-• and •BPh3R (R = Ph or Bu), in which the latter dissociates into Ph3B and R•, yielding biphenyl (or octane). Electron-donor ability of -BPh3 Bu is higher than that of -BPh4, while the steady-state photolysis to a C60/borate system shows an opposite tendency. The addition reaction of C60-• with Bu• yielding BuC60- is more efficient than that with Ph• producing PhC60-. The rate constant of electron-transfer via the triplet state of C60 increases with solvent polarity.
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U2 - 10.1039/a808120d
DO - 10.1039/a808120d
M3 - Article
AN - SCOPUS:0001224664
SP - 551
EP - 556
JO - Journal of the Chemical Society, Perkin Transactions 2
JF - Journal of the Chemical Society, Perkin Transactions 2
SN - 1470-1820
IS - 3
ER -