[3]Pseudorotaxane-Like Complexes Formed between Bipyridinium Dications and Bis-<i>p</i>-xylyl[26]crown-6

The crown ether BPX26C6 forms a [3]pseudorotaxane-like complex with the N,N‘-dimethyl-4,4‘-bipyridinium dication both in solution and in the solid state. The facile one-pot synthesis of a [2]rotaxane from neutral precursors−BPX26C6, 4,4‘-dipyridyl, and 3,5-di-tert-butylbenzyl bromide−suggests that BPX26C6 may bind to (mono)pyridinium cations in a [2]pseudorotaxane-like manner.