Unity Makes Strength:Constructing Polymeric Catalyst for Selective Synthesis of CO_(2)/Epoxide Copolymer

Catalyst design strategies such as bi-functional and di-nuclear catalysts have been developed based on intramolecular interactions,achieving excellent catalytic performance.However,most of these catalysts work in a state of disunity.To make progress in this direction,we reckoned that enhancing the neglected intermolecular interactions of these catalysts might be a suitable approach.Herein,we report a strategy of constructing homogeneous polymeric catalysts based on the philosophy of“unity makes strength”to convert the intermolecular interactions into stronger intramolecular interactions.We united discrete active centers of aluminum(Al)porphyrin and tertiary amine(methyl methacrylate;MMA)via a random copolymerization process into one polymer chain with the subsequent metallization using low-toxic metal AlEt_(2)Cl,to construct polymeric catalysts for selective copolymerization of CO_(2)/epoxide.The spatial confinement enabled the multiple interactions among the active centers,which was distinct from the“point-to-point”interacting systems such as binary,bi-functional,or di-nuclear complexes.Through detailed tuning of the multiple synergistic effects between porphyrin/porphyrin(metal synergistic effect)and Al porphyrin/tertiary amine(Lewis pair effect),the optimized polymeric catalyst showed significantly boosted catalytic activity of 4300 h^(−1),much higher than their mono-nuclear(∼0 h^(−1))and homo-polymeric(750 h^(−1))counterparts.Our present approach for designing polymeric catalysts based on multiple synergistic effects provides a platform for developing highly active catalysts.