Electrochemistry of the metallo-bisfullerene [Mo(eta(2)-C-60)(2)(CO)(2)(dbc-bipy)] (dbc-bipy=4,4 '-di(butylcarboxyl)-2,2 '-bipyridine)

Electrochemical investigations on the dumb-bell like [Mo(η2-C60 )2 (CO)2 (dbc-bipy)] show that the two fullerene subunits undergo a sequence of slightly separated stepwise reductions. The mutual electronic interaction of the two cages, which is responsible for the separation of the sequential electron additions, is comparable with that of C120 , C121 , C120 O, C122 H4 and C120 SiPh2 , which actually are the only symmetric bis-fullerenes able to display intramolecular electronic interactions. Changing the solvent (from CH2 Cl2 to THF) causes a slight increase in the stepwise reductions exhibited by [Mo(η2-C60 )2 (CO)2 (dbc-bipy)], thus supporting a Mo-mediated through-space communication between the two fullerene moieties.