Synthesis Methodology of End-Functionalized Poly(quinolylene-2,3-methylene)s: Living Cyclocopolymerization Using Aryl Palladium Initiators Conveniently Prepared from Versatile Aryl Halide
Naoya Kanbayashi, Kazuki Yamazaki, Miho Nishio, Kiyotaka Onitsuka
Abstract
The facile synthesis of end-functionalized poly(quinolylene-2,3-methylene)s using aryl palladium initiators conveniently prepared from versatile aryl halides has been reported. When various aryl palladium complexes with 1,3-bis(diphenylphosphino)propane, synthesized by the oxidative addition of an aryl halide to Pd(PPh3)4 and the ligand exchange reaction, were used as initiators, cyclocopolymerization of o-allenyl aryl isocyanide afforded poly(quinolylene-2,3-methylene)s with a narrow molecular weight distribution (Mw/Mn = 1.06–1.12), and each aryl group on the palladium complex was quantitatively introduced into the α-chain end. The end-functionalization system was successfully applied to a one-pot polymerization, which did not require the isolation of each aryl palladium complex. This method can be used for many aryl halides, including commercially available products, and has successfully obtained end-functionalized polymers with a wide variety of end functional groups, including bulky and reactive substituents. Furthermore, we expanded this system to synthesize block copolymers with polylactide and multiarmed polymers using initiators with multiple starting points.