Straightforward supramolecular purification of C84 from a fullerene extract

Selective purification of fullerene mixtures via supramolecular encapsulation is an appealing strategy to circumvent the tedious HPLC chromatographic purification protocols. In this work, we utilize tetragonal prismatic nanocapsules of different cavity sizes and shapes to selectively encapsulate C-84 from a mixture containing fullerenes ranging from C-60 to C-96 (fullerene extract), allowing the enrichment of the C-84 content from 0.7% to 86%. Moreover, terphenyl-based extra-large nanocapsules were prepared for the first time that can strongly bind the dumbbell-shaped azafullerene dimer (C59N)(2) as a guest. Competition experiments between (C59N)(2) and C-84 allowed the deduction of K-a > 1.0 x 10(7) M-1 for C-84 in nanocapsule 6 center dot(BArF)(8). The preference of nanocapsule 7 center dot(BArF)(8) to bind C-84-D-2(22) among all IPR-isomers is also discussed.