Monofunctionalized C60 Ions: Their Generation, Stability, and Reactions

Though numerous investigations have appeared on the reduced and oxidized forms of parent C60, investigations on C60 ions that contain exohedral functional group(s) have been rather few. This account deals with the chemistry of such ions, in particular, the chemistry of monofunctionalized species RC60− and RC60+. Studies of the anions RC60− were initiated early in the history of the fullerene chemistry, and they are generally considered appreciably stable carbanions. This account focuses on our recent synthesis of a hydrocarbon salt and ionically dissociable hydrocarbons which contain the C60 framework. These are unusual classes of hydrocarbons that could be obtained by making use of the high thermodynamic stability of a hydrocarbon anion t-BuC60−. Some of the properties which are characteristic of these hydrocarbons are also discussed. In contrast, studies of the chemistry of the cation RC60+ have only recently been launched. In this account, advances in the studies of these cations, including observations of their existence, the evaluation of their stabilities, and the role of these cations as a reactive intermediate, are described.