We report the binding constants of CB[7] toward a series of naphthalene diammonium and 4,4′-dipiperidinium derivatives and compare the results with those obtained previously for CB[7]·3b by 1H NMR and X-ray crystallography. The nature of binding in the host·guest complexes was investigated using quantum mechanical tools.
![Graphical abstract: Influence of hydrophobic residues on the binding of CB[7] toward diammonium ions of common ammonium⋯ammonium distance](http://hg.y866.cn/compound/lib/scimg/usr/1/C5OB00784D.jpg)
