Functionalized Polyesters via Stereoselective Electrochemical Ring-Opening Polymerization of O-Carboxyanhydrides
Ring-opening polymerization is used to prepare polyesters with precisely controlled molecular weights, molecular weight distributions, and tacticities. Herein, we report a newly developed Co/Zn catalytic system that can be activated by an electrical current to mediate efficient ring-opening polymerization of enantiopure <i>O</i>-carboxyanhydrides, allowing for the synthesis of isotactic functionalized polyesters with high molecular weights (>140 kDa) and narrow molecular weight distributions (<i>M</i><sub>w</sub>/<i>M</i><sub>n</sub> < 1.1). We also demonstrate that these catalysts can be used for stereoselective ring-opening polymerization of racemic <i>O</i>-carboxyanhydrides to synthesize syndiotactic or stereoblock copolymers with different glass transition temperatures compared with their atactic counterparts.