Towards Rotaxane-Based Metal-Ion Sensors

The self-assembly and dynamic behaviour of rotaxanes [1] is a fascinating outcome of supramolecular chemistry, which has enabled the genesis of simple molecular switches in the form of molecular shuttles [2,3]. We are now directing our attention towards the design and synthesis of metal-ion sensors using rotaxane-based compounds. The design logic for such sensors is based upon recent studies in our laboratory [4] which indicate that a solution containing equimolar quantities of the π-electron rich ‘threads’ 1 and 2, and a tetracationic cyclophane 3 4PF6 is capable of acting as a K + ion sensor.