Research

CASC will enable the supramolecular control, transport and transformation of oxy and fluorinated anions, a widely recognized and longstanding challenge. The two targeted anions, bicarbonate and PFOA, represent two extremes in terms of size, shape, and solvation, features that will aid in the establishment of fundamental supramolecular principles applicable to a broad chemical landscape. Supramolecular recognition of anions will be manifested via the incorporation of fluxional receptors whose primary recognition motifs are unique ionic, hydrogen, or halogen bonds that are exquisitely sensitive to the local electronic and electrostatic environment. CASC will demonstrate that by adjusting these forces within supramolecular host guest complexes, both the affinity and selectivity of the host guest complexes can be manipulated to enable the design of a new class of switchable receptors. By exploiting electronic and electrostatic forces between a host and its guest, on-demand allosteric control over both the binding and release processes will be established for the transport of ions across lipid bilayer or polymeric membranes. Switchable supramolecular receptors will be utilized as directing agents to improve the reactivity of catalysts and foster transformation. Bicarbonate receptors will be conjugated to reduction catalysts that include iron and iridium complexes, and PFOA receptors will be grafted onto alumina or conjugated with photobases such as malachite green carbinol molecules.  The ability to control both affinity and selectivity will propel anion supramolecular chemistry into novel domains that extend beyond recognition and sensing. A newfound capability to simultaneously transport and transform anions in water will impact environmental chemistry, chemical biology, and catalysis.