Facile preparation of Cobaltocenium-containing polyelectrolyte via click chemistry and RAFT polymerization

A facile method to prepare cationic cobaltocenium-containing polyelectrolyte is reported. Cobaltocenium monomer with methacrylate is synthesized by copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction between 2-azidoethyl methacrylate and ethynylcobaltocenium hexafluorophosphate. Further controlled polymerization is achieved by reversible addition- fragmentation chain transfer polymerization (RAFT) by using cumyl dithiobenzoate (CDB) as a chain transfer agent. Kinetic study demonstrates the controlled/living process of polymerization. The obtained side-chain cobaltocenium-containing polymer is a metal-containing polyelectrolyte that shows characteristic redox behavior of cobaltocenium. A facile synthesis method to functional cobaltocenium-containing polyelectrolyte is reported. By using click chemistry and RAFT, the functional cationic cobaltocenium polymer is prepared from un-substituted cobaltocenium. The obtained polymer shows characteristic UV-vis absorption peaks and redox properties of the cobaltocenium group.