Halogen bonding hosts for anion recognition and extraction

The chemical recognition of anions has progressed enormously in the last 20 years, partially in response to the ubiquity of anions in a vast range of biological, environmental and industrial processes.1,2 However it has only been recently demonstrated that halogen bonding, comparable to hydrogen bonding in terms of its binding strengths and directionality, is a powerful alternative non-covalent interaction for the purposes of solution phase anion recognition. It is therefore desirable to explore the possibility of using halogen bonding for the purposes of water remediation, since the impacts of anthropological activity to the environment, especially the water cycle, are significant.
Aims and Objectives - To incorporate halogen bonding motifs into both acyclic and interlocked organic scaffolds for anion recognition investigations in water and extraction of environmentally important anions from aqueous effluent.
Despite the demonstrated ability of halogen bonding to perform in competitive solvent media as an effective tool in anion recognition, halogen bonding systems operating in water are extremely rare, with only two previous examples reported. Further exploitation of novel halogen bonding motifs will generate more information on this interaction in aqueous media and facilitate a real world application of halogen bonding to water purification, which is of global significance.
This project falls within the following EPSRC research areas: Global Uncertainties, Living With Environmental Change, Manufacturing the future, Healthcare technologies and Physical Sciences.
In collaboration with Johnson Matthey the halogen bonding scaffold design will facilitate the attachment of halogen bonding lipophilic receptor analogues to silica or polymer materials to produce novel extractants for toxic anions.