DISTORTION OF THE CUCURBITURIL MOLECULE BY AN INCLUDED 4-METHYLPYRIDINUM CATION

The crystal and molecular structures of a “guest–host” complex of cucurbituril with 4‐methylpyridinium, {(4‐MePyH) ⊂ (C36H36N24O12)}(NO3) · 4H2O, were determined by X‐ray structural analysis. The crystals are monoclinic with a = 26.276(3) A, b = 25.861(2) A, c = 17.375(2) A, β = 124.17(1)°, Vcell =9768.6(18) A3, space group Cc, and Z = 8. The structure contains two crystallographically independent supramolecular complexes. They are arranged in pillars oriented along the a axis. In each pillar, the complexes are parallel to each other. The pillars are shifted with respect to each other by one‐half of the crystallographic translation. The centers of the supermolecules are arranged according to a pseudo‐body‐centered motif. Distortions of the cucurbituril molecule depending on the guest type have been analyzed with the use of results obtained in the present and previous studies.