Expanding monomer scope and enabling post-modification in photocontrolled radical ring-opening polymerization of vinylcyclopropanes by an iodine transfer strategy

Abstract

Although visible-light photoredox catalysis can implement diverse reaction mechanisms for the synthesis of well-defined polymers with precise spatiotemporal control, the tolerance of redox-sensitive monomers remains a formidable challenge. Alternatively, a photoiniferter polymerization technique offers an opportunity to address this obstacle. Herein, we report an efficient iodine-transfer radical ring-opening polymerization of vinylcyclopropanes (VCPs), affording unsaturated linear polymers with predictable molecular weight and low dispersity. Commercially available alkyl iodide and light strips are used to initiate and control the polymer chain growth. Notably, this light-driven system tolerates active pentafluorophenyl ester groups, whereby nearly quantitative post-modifications proceed and have rendered a one-for-all preparation of polymers including crystalline semi-fluorinated P(VCPs) with enhanced material properties.