Inherently chiral conducting polymer film electrodes

The availability of materials able to couple electroactivity and enantiorecognition capability is an ambitious objective of the current chemical research, aiming to both electrically triggered enantioselective electron transfers and electrically monitored enantioselective recognitions. Ideal candidates are organic conducting polymers, several of which have been functionalized with chiral pendants; this "localized" approach, however, appears to lead to poor chirality manifestations. We present inherently chiral conducting polymer films prepared by electropolymerization of monomers like the TX molecule in the figure, where chirality is owed to a tailored torsion internally produced along the whole conjugated backbone, and not to the presence of stereocentres external to the conjugated chain. Both enantiomer films have been characterized together with the racemate one by CV, EIS, and circular dichroism with in-situ electrochemistry. Positive charge injection, reducing the torsion angle to achieve better p system conjugation, results in a fully reversible "breathing" process of the 3D chiral conducting network upon potential cycling. Enantiorecognition capability tests on chiral probe molecules are in progress.