Fullerene cations chemistry

During the past 15 years since Qo became available in macroscopic quantities in 1990 [1], a wide variety of its derivatives have been synthesized as part of the explosive development of the study of its chemistry [2). Various organic reactions have been reported, most of which are cycloadditions, nucleophilic additions, and radical additions. Fullerenes, as represented by Qo, are now commonly accepted to behave as electron-deficient olefins, hence there have been numerous studies on their anions. This has led to a situation where the other equally important species, the fullerene cations, have been left unexplored for nearly a decade in spite of their significance in both fundamental and application studies. Clearly, a systematic study of this class of species is needed. 

In contrast to the high stability of anionic species, cations possessing a positive charge on the -conjugated system of a fullerene cage are uncommon. The chemistry of such cations have remained unexplored for nearly a decade, since C6o became available in macroscopic quantities in 1990 (70), in spite of their potential significance in both fundamental and application studies. 

Marchesan S, Da Ros T, Spalluto G, Balzarini J, Prato M (2005) Anti-HIV properties of cationic fullerene derivatives. Bioorganic and Medicinal Chemistry Letters 15 3615-3618. 

Mashino, T., Nishikawa, D., Takahashi, K.> Usui> N., Yamori, T., Seki, M., Endo, T, Mochizuki, M. (2003). Antibacterial and antiproliferative activity of cationic fullerene derivatives. Bioor-ganic and Medicinal Chemistry Letters, 13, 4395-4397. 

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