Post‐Synthetic Modification of a Porous Hydrocarbon Cage to Give a Discrete Co(24) Organometallic Complex

A new alkyne‐based hydrocarbon cage was synthesized in high overall yield using alkyne‐alkyne coupling in the cage forming step. The cage is porous and displays a moderately high BET surface area (546 m(2) g(−1)). The cage loses crystallinity on activation and thus is porous in its amorphous form, while very similar cages have been either non‐porous, or retained crystallinity on activation. Reaction of the cage with Co(2)(CO)(8) results in exhaustive metalation of its 12 alkyne groups to give the Co(24)(CO)(72) adduct of the cage in good yield.