Ion-pair recognition by a neutral [2]rotaxane based on a bis-calix[4]pyrrole cyclic component.

ABSTRACT: In this work, we report our investigations on the synthesis of a [2]rotaxane based on a bis(calix[4]pyrrole) cyclic component and a 3,5-bis-amidepyridyl-N-oxide derivative axle. We isolated the [2]rotaxane in a significant 50% yield through an optimized "in situ" capping strategy using the copper(i)-catalyzed azide-alkyne cycloaddition reaction. The synthetic precursor of the [2]rotaxane, featuring [2]pseudorotaxane topology, could be quantitatively assembled in solution in the presence of one equivalent of tetrabutylammonium chloride or cyanate salts producing a four-particle aggregate. However, we observed that the addition of the salt was deleterious not only for the isolation of the [2]rotaxane in its pure form but, more important, for the optimal performance of the coppe

SUBMITTER: Romero JR 

PROVIDER: S-EPMC5341206 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature