| Abstract
| - tert-Butylperoxy radicals add to C60 selectively to form multi-adducts C60(O)m(OOtBu)n (m = 0, n =2, 4, 6; m = 1, n = 0, 2, 4, 6) in moderate yields under various conditions. Visible light irradiationfavors epoxide formation. High concentration of tert-butylperoxy radicals mainly produces the hexa-homoadduct C60(OOtBu)66; low concentration and long reaction time favor the epoxy-containingC60(O)(OOtBu)47. The reaction can be stopped at the bis-adducts with limited TBHP. A stepwiseaddition mechanism is discussed involving mono-, allyl-, and cyclopentadienyl C60 radical intermediates. m-CPBA reacts with the 1,4-bis-adduct to form C60(O)(OOtBu)2 and C60(O)3(OOtBu)2. The C−Obond of the epoxy ring in 7 can be cleaved with HNO3 and CF3COOH. Nucleophilic addition ofNaOMe to 7 follows the SN1 and extended SN2‘ mechanism, from which four products are isolatedwith the general formula C60(O)a(OH)b(OMe)c(OOtBu)d. Visible light irradiation of the hexa-adduct6 results in partial cleavage of both the C−O and O−O bonds of peroxide moieties and formationof the cage-opened compound C60(O)(O)2(OOtBu)4. All the fullerene derivatives are characterizedby spectroscopic data. A single-crystal structure has been obtained for an isomer of C60(O)(OH)2(OMe)4(OOtBu)2.
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