Nonradical Light-Controlled Polymerization of Styrene and Vinyl Ethers Catalyzed by an Iridium-Palladium Photocatalyst

A visible-light-sensitive Ir-Pd photocatalyst is effective for coordination copolymerization of styrene and vinyl ethers. The catalyst drastically accelerates styrene polymerization under visible light irradiation and allows sequence-controlled copolymerization of styrene and vinyl ethers by appropriate switching of the irradiation sequence. The reaction rates of the monomers under irradiated and nonirradiated conditions were compared. Mechanistic studies suggested that the reactions proceeded via a nonradical coordination-insertion mechanism.