The design and synthesis of receptors that have the ability to selectively bind and sense neutral and ionic species is a new emerging topical field of supramolecular chemistry. The importance of spatial pre-organisation of the complexing groups has been recognized and calixarenes in particular have been developed as structures for the preparation of selective receptors [1]. The versatility of calixarenes has been extensively used as their scaffolds present a hydrophobic aromatic core that can be functionalized easily at both the upper and lower rims [2]. Such receptors are generally achieved through combining well-defined recognition centers with signalling moieties to enable detection of ion binding via optical and electrochemical methods [3]. We present here a ferrocene reporting unit that has been successfully incorporated onto the lower-rim of calix[4]arene through click chemistry. This novel redox-active receptor is expected to be used as an electrochemical sensor to recognize ions with a good selectivity. The new ferrocene-based calix[4]arene was characterized by 1H and 13C NMR spectra. The details of this procedure and characterization of receptor will be reported during the Seminar.
