Separation and Selective Formation of Fullerene Adducts within an MII8L6 Cage

The self-assembly of 4-fold-symmetric porphyrins with Fe-II or Zn-II gave a new cubic (M8L6)-L-II cage framework with electron-deficient walls. This cage bound C-60-indene or C-60-anthracene bisadducts selectively, whereas unfunctionalized fullerenes and monoadducts were not encapsulated. The (Fe8L6)-L-II cage also enabled the reaction of C-60 and anthracene to yield the bisadducts selectively under conditions where no reaction was observed in the absence of the cage. These findings have relevance in the context of polymer solar cells, where C-60 bisadducts have found use as electron acceptors, because these adducts currently require laborious and timeconsuming syntheses and purification.