Double-Holed Fullerenes.

Fully-fused caged nanocarbons with multiple orifices are segmental structures of porous carbon frameworks long envisioned as synthetic targets of interest. Conventional bottom-up approaches, however, could not overcome the high strain energies required for graphitic precursors to be rounded up. Herein, we report a top-down approach to produce fully-fused carbon nanoelbows as double-holed fullerenes derived from strained C60. The concise one-pot synthesis featuring unique selectivity enabled the isolation of six compounds, while orifice sizes were modifiable from 8- to 12-membered rings and vice versa. The crystallographic analysis confirmed their elbow-shaped structures with different curvatures. Within the crystal, cylindrical nanoporous arrangement were found with the inclusion of solvent guests, reminiscent of hypothetical fullerene sponges.