An electron-rich three dimensional receptor based on a calixarene-tetrathiafulvalene assembly

The synthesis of a calix[4]arene scaffold persubstituted with four redox-active tetrathiafulvalene (TTF) moieties at the lower rim is described. This assembly strongly binds sodium cation, and the binding process is accompanied by a conformational change of the receptor, as shown from NMR titration and by an X-ray diffraction led on the complex. This dynamic behavior remarkably results in a modification of the electrochemical response of TTF probes, which behave independently after sodium complexation.