Two [2]pseudorotaxane-like complexes and their corresponding [2]rotaxanes stabilized via interactions on opposite ends of the same macrocycle

A multiple-use macrocycle recognizes dibenzylammonium ions and 2,6-lutidine derivatives, each in a [2]pseudorotaxane-like manner, through interactions with its diethylene glycol (hydrogen bonding) and 2,6-pyridinedicarboxamide (Pd2+ chelation) spacers, respectively. We characterized these complexes in the solid state (X-ray crystallography) and in solution (1H NMR spectroscopy). The synthesis of two corresponding [2]rotaxanes confirmed that these recognition systems possess [2]pseudorotaxane geometries in solution.