The cavity of the spherical frustum shapes endows belt compounds with potential in recognition of buckminsterfullerene. From UV-vis titration experiments (Figs. S21-S23), we found belt[8]pyrrole[8]pyridine 5c formed a 2:1 host-guest complex with C60 in 1,2-dichlorobenzene giving an extraordinary high binding constant (K2:1) of (3.07±0.06)×10 13 M -2 . Slow vapor diffusion of 1,2-dimethoxyethane into a solution of 5c and C60 in toluene at ambient temperature afforded a high-quality single crystal, and the molecular structure of host-guest complex was determined unambiguously with X-ray diffraction analysis. As revealed by the X-ray structure shown in Fig. , host and guest formed a complex in a 2:1 stoichiometry, which is identical to that in solution.