Multifunctional linear and hyperbranched five-membered cyclic carbonate-based polymers directly generated from co₂ and alkyne-based three-component Polymerization

Fixing carbon dioxide (CO₂) into polymeric materials is a subject of enduring interest but limited to very few efficient polymerizations. In this work, a facile Pd(OAc)₂/LiO^tBu-catalyzed one-pot, three-component polymerization of CO₂, bis(propargylic alcohol)s, and aryl dihalides under atmospheric pressure is developed. Linear and hyperbranched multifunctional five-membered cyclic carbonate (5CC)-based polymers with well-defined structures, high weight-Average molecular weights (M_w up to 42500), and versatile properties such as aggregation-induced emission as well as chiral and porous properties are successfully produced in excellent yields (up to 96%). The reaction mechanism was well investigated via the density functional theory calculation and in situ Fourier transform infrared spectroscopy, both indicating that there is synergistic reaction effect among CO₂, bis(propargylic alcohol)s, and aryl dihalides. The polymers could be postfunctionalized by amines via catalyst-free regioselective ring-opening reaction with 100% grafting ratio. Thus, this work not only develops a new way to directly fix CO₂ into polymeric materials but also provides the 5CC-based polymers with versatile properties, showing great potentials in diverse areas.