The self-assembly of complexes with [2]pseudorotaxane superstructures

The application of X-ray crystallography, mass spectrometry, and NMR and UV–VIS spectroscopy has revealed that bis-p-phenylene-34-crown-10 1 forms strong 1 : 1 complexes with the 4,4′-bipyridinium dication 32+ and two of its derivatives, namely, the dications 42+ and 52+ in which the substituents on the bipyridine nitrogen atoms are, respectively, 2-hydroxyethyl and 2-(2-hydroxyethoxy)ethyl groups.