摘要:
Electron-transfer reactions with C-60 leading to the singly reduced and oxidized radical ions, C-60(.-) and C-60(.+) have been studied by pulse radiolysis. pi-Radical anions of several metalloporphyrins (tetraphenyl- and tetrapyridylporphyrins) reduced C-60 With rate constants of (1-3) x 10(9) L mol(-1) s(-1), whereas metalloporphyrins which are reduced at the metal center (Ni-I, Cu-I, Cr-II) reacted with C-60 somewhat more slowly, with rate constants of (0.7-2.3) x 10(8) L mol(-1) s(-1). Sb(V)OEP(.-) (octaethylporphyrin) did not reduce C-60 (k less than or equal to 10(7) L mol(-1) s(-1)) and Sn-IV(Ph)(3)(Py)P-.- reacted in an equilibrium process (K = 14). Electron transfer from C-60 to several aromatic radical cations (derived from naphthalene, biphenyl, m-terphenyl, and trans-stilbene) also took place rapidly (k = (2.5-7.9) x 10(9) L mol(-1) s(-1)) to produce C-60(.+); the radical cations of anthracene and chrysene, on the other hand, did not exhibit any significant reactivity toward C-60.