Abstract 4-Aminobipyridine derivatives form strong inclusion complexes with cucurbit [6] uril, exhibiting remarkably large enhancements in fluorescence intensity and quantum yields. The remarkable complexation-induced pK a shift (ΔpK a= 3.3) highlights the strong charge– dipole interaction upon binding. The reversible binding phenomenon can be used for the design of switchable beacons that can be incorporated into cascades of binding networks. ...
