Photochemical reactions between C60 and aromatic thiols via electron transfer from aromatic thiols to the excited triplet state of C60 (3C60*) have been studied by means of laser flash photolysis. In polar benzonitrile, accompanied by the decay of 3C60*. the rise of the anion radical of C60 (C60•-) was observed for thiols, phenols, and disulfides with NH2 substituents. In the case of aminobenzene disulfide, the cation radical was observed at the same time as C60•-, which decayed by back electron transfer. For aminobenzenethiols, the free thio radical was observed, indicating fast deprotonation of the cation radicals of thiols. By the repeated laser-pulse irradiation of C60 in the presence of the aminobenzenethiols, the characteristic absorption bands of the monoadduct with C60 were observed, suggesting that the monoadduct is formed via electron transfer followed by consecutive radical coupling and protonation reactions. The rate constant of protonation of C60•- was also determined, which supports the proposed reaction mechanism.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry