Electropolymerization of hydrophobic dipyrrolyls in aqueous medium based on inclusion chemistry

Abstract

The host-guest complexation of hydrophobic dipyrrolyl monomers 1-4 with β-cyclodextrin has been studied in aqueous solution by means of ¹ H NMR spectroscopy, chemical analysis and electrochemical techniques. In each case, 1:2 stoichiometry is found, the cyclodextrin cavities being likely located on the extremities of the monomers. Polymeric materials were obtained from such inclusion compounds in water by either electrochemical or chemical oxidation. ESCA and elemental analyses show that the host molecule is absent from these polymers, whose characteristics are quite similar to those synthesized in organic media. A scheme for polymerization in the presence of cyclodextrin is proposed.