Open‐Cage Fullerene as a Selective Molecular Trap for LiF/[BeF]⁺

Abstract

The insertion of ionic compounds into opencage fullerenes is a challenging task due to the electropositive nature of the cavity. The present work reports the preparation of an open-cage C 60 derivative with a hydroxy group pointing towards the centre of the cavity, which can coordinate to a metal cation, thus acting as a bait/hook to trap the metal cation such as the lithium cation in neutral LiF and the beryllium cation in the cationic [BeF] + species. Other metal salts could not be inserted under similar conditions. The structure of MF in the cage was unambiguously determined by singlecrystal X-ray diffraction. Owing to its tendency to undergo polycoordination, Li + monomer salts have not been isolated before, despite extensive research on Li bonds. The present results provide a unique example of a Li bond.