Phase-transfer catalysis in the oxidation of C60 and C70 fullerene with KMnO4 and crown ether

Abstract

ABSTRACTThe KMnO4 oxidation reaction of C60 or C70 fullerenes in benzene solution proceeds smoothly and almost quantitatively in presence of the crown ether 18-crown-6 as phase-transfer agent. The oxidation reaction was followed spectrophotometrically from the early stages to the completion. Essentially fullerenols or polyhydroxylated fullerenes were produced as confirmed also by FT-IR spectroscopy. The resulting degree of hydroxylation of both C60 and C70 was determined as C60(OH)28 and C70(OH)26. As secondary structures, also epoxide and carboxylic groups were detected.