Visible-light-induced synthesis of polymers with versatile end groups mediated by organocobalt complexes

Synthesis of polymers with well-defined functional groups at α and ω ends remains a major challenge in polymer chemistry. We report a versatile method to prepare polymers with various functional groups at α ends without tedious post-modification by using carefully designed organocobalt complexes ((salen)Co-R) as the catalyst. The ω ends of (salen)Co were further functionalized to the hydroxyl group. Both of the more active monomers (MAM; acrylates and acrylamides) and less active monomers (LAM; vinyl acetate) could be controlled to produce homo and various block copolymers with a predetermined molecular weight, narrow polydispersity and high level of polymer end fidelity under visible light irradiation. More importantly, the polymers are prepared and functional groups are installed simultaneously during the propagation process, including alkynyl, tert-butyl, phenyl, cyclohexyl, fluoride, chloride, furyl, or thienyl groups at the α ends.