The development of artificial anion receptors is among the most vibrant research areas in supramolecular chemistry nowadays.[1] Such receptors have potential for applications in, for example, analyte sensing, waste extraction and membrane transport. In view of this, dynamic control of the binding affinity may be advantageous: It would facilitate recyclability of the receptor and allow transport processes to be activated and deactivated on demand. Hence, different methods to modulate anion binding properties have been developed,[2] but still, it remains highly challenging to obtain sizeable differences in binding affinity between the different addressable states. We have designed and synthesized stiff-stilbene based anion receptors that can be switched by light between very distinct affinity modes.[3,4]. When the stiff-stilbene photoswitch was functionalized with urea binding motifs, for example, it bound strongly and selectively toward oxo-anions (i.e. acetate and dihydrogen phosphate) in the (Z)-form, while binding to the (E)-isomer was considerably lower. Furthermore, a calix[4]pyrrole receptor that was strapped with stiff-stilbene, displayed an unparalleled 8000-fold affinity difference for chloride between the photoaddressable states. These receptors are currently being studied as extractants and transmembrane carriers by our group.

Effective control of anion binding using light-switchable receptors

ACS Fall 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.