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Intermolecular interactions that involve aromatic rings are key processes in both chemical and biological recognition. It is common knowledge that the existence of anion–π interactions between anions and electron‐deficient (π‐acidic) aromatics indicates that electron‐rich (π‐basic) aromatics are expected to be repulsive to anions due to their electron‐donating character. Here we report the first concrete theoretical and experimental evidence of the anion–π interaction between electron‐rich alkylbenzene rings and a fluoride ion in CH₃CN. The cyclophane cavity bridged with three naphthoimidazolium groups selectively complexes a fluoride ion by means of a combination of anion–π interactions and (CH)⁺⋅⋅⋅F⁻‐type ionic hydrogen bonds. ¹H NMR, ¹⁹F NMR, and fluorescence spectra of 1 and 2 with fluoride ions are examined to show that only 2 can host a fluoride ion in the cavity between two alkylbenzene …