We describe the use of polyatomic anions for the quantitative assembly of ion-paired complexes displaying pseudorotaxane topology. Our approach exploits the unique ion-pair recognition properties exhibited by noncovalent neutral receptors assembled through hydrogen-bonding interactions between a bis-calix[4]pyrrole macrocycle and linear bis-amidepyridyl-N-oxides. The complexation of bidentate polyatomic anions that are complementary in size and shape to the receptor’s cavity, in which six NH hydrogen-bond donors converge, induces the exclusive formation of four particle-threaded assemblies.
![Polyatomic anion assistance in the assembly of [2]pseudorotaxanes](https://www.iciq.org/wp-content/uploads/2014/03/Polyatomic-anion-assistance_10733.gif)