Electrocatalytic properties of the $C60,$ $C70,$ $C76,$ $C78$ and $C84$ fullerene anions Available to Purchase

Di- and trianions of the title fullerenes reduce electrocatalytically 1,2 -dihaloethanes. The fullerene anions were generated electrochemically in 0.1 M tetra-n-butylammonium hexafluorophosphate benzonitrile solutions of the 1,2-dihaloethanes. Cyclic voltammetry experiments indicate that the electrocatalytic reduction results in dehalogenation of the 1,2-dihaloethanes in case of dianions of $C60,$ $C70,$ $C76$ and $C78$ as well as trianions of $C76C78$ and $C84.$ Values of the second-order rate constant, k, for the electrocatalytic processes were determined by using a rotating-disk electrode voltammetry under pseudo-first-order conditions against the 1,2-dihaloethanes. The k values increase in the order: $Cl<Br<I$ for each fullerene anion and in the order: $C60<C70<C76<C78<C84$ for each 1,2-dihaloethane. In contrast to the $C60n−$ electrocatalysis, no alkyl adducts were formed in case of the larger fullerene anions. Due to higher stability with respect to the adduct formation and more positive potentials of the electrocatalytic processes, the larger fullerene anions may serve as more useful catalysts than the $C60$ anions despite that the respective electrocatalytic rate constants are smaller.