Efficient Kinetic-Resolution Copolymerization of Epoxides and CO<sub>2</sub> Achieved via Computation-Guided Catalyst Design
Bai‐Hao Ren, Sarah M. Severson, Sinuo Wang, Zheng‐Fei Liu, Lin-Di Zhang, Zi-Cong Wang, Ye Liu, Wei‐Min Ren, Geoffrey W. Coates, Xiao‐Bing Lu
Abstract
The enantioselective resolution copolymerization of racemic terminal epoxides and CO 2 is a powerful strategy for preparing isotactic polycarbonates. However, no catalytic system to date has enabled both high chemo- and stereoselectivity in this transformation. Herein, a computation-guided strategy was conducted to understand the key factors governing the activity, chemoselectivity, and stereoselectivity of chiral bimetallic cobalt complexes. Computational fine-tuning of bimetallic synergy allowed accelerated copolymerization, suppression of epoxide homopolymerization, and enhanced chiral induction. Ultimately, a privileged chiral bimetallic catalyst bearing 6,6-ditriflate substituents was computationally designed and experimentally synthesized, which exhibited unprecedented enantioselectivity ( s -factor up to over 300) and high chemoselectivity (>95% carbonate units) for various racemic epoxides during resolution copolymerization with CO 2 . This study is expected to serve as a theoretical framework for broadly guiding the design of privileged chiral catalysts for asymmetric catalytic polymerizations.