An all-halogen bonding rotaxane for selective sensing of halides in aqueous media

Benjamin R Mullaney; Amber L Thompson; Paul D Beer

doi:10.1002/anie.201403659

An all-halogen bonding rotaxane for selective sensing of halides in aqueous media

Angew Chem Int Ed Engl. 2014 Oct 20;53(43):11458-62. doi: 10.1002/anie.201403659. Epub 2014 Jul 7.

Authors

Benjamin R Mullaney¹, Amber L Thompson, Paul D Beer

Affiliation

¹ Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA (UK).

PMID: 25044414
DOI: 10.1002/anie.201403659

Abstract

The synthesis and anion binding properties of the first rotaxane host system to bind and sense anions purely through halogen bonding, is described. Through a combination of polarized iodotriazole and iodotriazolium halogen bond donors, a three-dimensional cavity is created for anion binding. This rotaxane incorporates a luminescent rhenium(I) bipyridyl metal sensor motif within the macrocycle component, thus enabling optical study of the anion binding properties. The rotaxane topology was confirmed by single-crystal X-ray structural analysis, demonstrating halogen bonding between the electrophilic iodine atoms and chloride anions. In 50% H2O/CH3CN solvent mixtures the rotaxane host exhibits strong binding affinity and selectivity for chloride, bromide, and iodide over a range of oxoanions.

Keywords: anions; halogen bonding; noncovalent interactions; rotaxanes; supramolecular chemistry.