Complexation of an Anthracene‐Triptycene Nanocage Host with Fullerene Guests through CH···π Contacts

Kazuki Kajiyama, Eiji Tsurumaki, Kan Wakamatsu, Gaku Fukuhara, Shinji Toyota

A bicyclic anthracene macrocycle containing two triptycene units at the bridgehead positions was synthesized by Ni-mediated coupling of the corresponding precursor as a cage-shaped aromatic hydrocarbon host. This cage host formed an inclusion complex with C60 or C70 guest in 1 : 1 ratio in solution. The association constants (Ka ) determined by the fluorescence titration method were 1.3×104 and 3.3×105  L mol -1 for the C60 and C70 complexes, respectively, at 298 K in toluene. DFT calculations revealed that the guest molecules were included in the middle of the cavity with several CH⋅⋅⋅π contacts. The strong affinity of the cage host for the fullerene guests and the high selectivity toward C70 are discussed on the basis of spectro scopic and structural data.

ChemPlusChem

86

5

716

722

10.1002/cplu.202000816