查看更多>>摘要：Catalyst design strategies such as bi-functional and di-nuclear catalysts have been developed based on intramolecular interactions,achieving excellent cat-alytic 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 stron-ger intramolecular interactions.We united discrete active centers of aluminum(AI)porphyrin and tertia-ry amine(methyl methacrylate;MMA)via a random copolymerization process into one polymer chain with the subsequent metallization using low-toxic metal AIEt2Cl,to construct polymeric catalysts for selective copolymerization of CO2/epoxide.The spa-tial confinement enabled the multiple interactions among the active centers,which was distinct from the"point-to-point"interacting systems such as bi-nary,bi-functional,or di-nuclear complexes.Through detailed tuning of the multiple synergistic effects between porphyrin/porphyrin(metal synergistic ef-fect)and AI 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 h1)counterparts.Our present approach for designing polymeric catalysts based on multiple synergistic effects provides a platform for developing highly active catalysts.
查看更多>>摘要：Integrating catalytic reactions with molecular assem-bly is a promising means of achieving controllable supramolecular polymerization.We report herein a novel and controllable method for in situ supramole-cular polymerization via organometallic-catalyzed macromolecular metamorphosis.To this end,covalent polymers with polypentenamer backbones and pen-dant supramolecular motifs are designed and synthe-sized.By depolymerizing the polymers with Grubbs catalysts,the supramolecular motifs can be gradually released from the polymers to the solution.Supramo-lecular polymerization occurs when a critical concen-tration is reached.The supramolecular polymerization process was readily controlled by varying the rate of the depolymerization reaction.This work presents a novel approach that uses organometallic catalysis to transform covalent polymers into supramolecular polymers.It offers a new means of constructing com-plex molecular systems in a controllable manner.
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