An electrochemical approach to aluminum-based redox switchable ring opening polymerization

We report the electrochemically switchable reactivity of (salfen)Al(OiPr) (salfen = 1,1′-di(2,4-bis-tert-butyl-salicylimino)ferrocene) toward the ring opening polymerization of various cyclic esters, ethers, and carbonates. Using a recently developed electrochemical system comprised of an H-cell and glassy carbon working electrode, an applied potential can alternate between two redox states of the catalyst and alter monomer incorporation during ring opening polymerization. We discuss differences in activity and control under electrochemical conditions compared to previously studied chemical redox methods and discuss the necessity of a redox switch during certain copolymerization reactions.