Tetranuclear N-Methyl Aminodiethylate Aluminum Complexes as Efficient Catalysts for Ring-Opening Polymerization of Substituted Epoxides
Yu Chen
State and Local Joint Engineering Laboratory for Novel Functional Department Polymeric Materials, Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake Campus, Soochow University, Suzhou, Jiangsu, 215123 China
Search for more papers by this authorYanwei Wang
State and Local Joint Engineering Laboratory for Novel Functional Department Polymeric Materials, Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake Campus, Soochow University, Suzhou, Jiangsu, 215123 China
Search for more papers by this authorYanping Song
State and Local Joint Engineering Laboratory for Novel Functional Department Polymeric Materials, Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake Campus, Soochow University, Suzhou, Jiangsu, 215123 China
Search for more papers by this authorCorresponding Author
Xuehua Zhu
School of Chemistry and life Science, Suzhou University of Science and Technology, Suzhou, Jiangsu, 215009 China
E-mail: [email protected]; [email protected]; [email protected]Search for more papers by this authorCorresponding Author
Dan Yuan
State and Local Joint Engineering Laboratory for Novel Functional Department Polymeric Materials, Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake Campus, Soochow University, Suzhou, Jiangsu, 215123 China
E-mail: [email protected]; [email protected]; [email protected]Search for more papers by this authorCorresponding Author
Yingming Yao
State and Local Joint Engineering Laboratory for Novel Functional Department Polymeric Materials, Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake Campus, Soochow University, Suzhou, Jiangsu, 215123 China
E-mail: [email protected]; [email protected]; [email protected]Search for more papers by this authorYu Chen
State and Local Joint Engineering Laboratory for Novel Functional Department Polymeric Materials, Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake Campus, Soochow University, Suzhou, Jiangsu, 215123 China
Search for more papers by this authorYanwei Wang
State and Local Joint Engineering Laboratory for Novel Functional Department Polymeric Materials, Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake Campus, Soochow University, Suzhou, Jiangsu, 215123 China
Search for more papers by this authorYanping Song
State and Local Joint Engineering Laboratory for Novel Functional Department Polymeric Materials, Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake Campus, Soochow University, Suzhou, Jiangsu, 215123 China
Search for more papers by this authorCorresponding Author
Xuehua Zhu
School of Chemistry and life Science, Suzhou University of Science and Technology, Suzhou, Jiangsu, 215009 China
E-mail: [email protected]; [email protected]; [email protected]Search for more papers by this authorCorresponding Author
Dan Yuan
State and Local Joint Engineering Laboratory for Novel Functional Department Polymeric Materials, Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake Campus, Soochow University, Suzhou, Jiangsu, 215123 China
E-mail: [email protected]; [email protected]; [email protected]Search for more papers by this authorCorresponding Author
Yingming Yao
State and Local Joint Engineering Laboratory for Novel Functional Department Polymeric Materials, Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake Campus, Soochow University, Suzhou, Jiangsu, 215123 China
E-mail: [email protected]; [email protected]; [email protected]Search for more papers by this authorComprehensive Summary
Polyether materials, derived from the ring-opening polymerization (ROP) of epoxides, are widely used in biomedicine and functional materials. However, due to the steric hindrance of the high-freedom substituents, monosubstituted epoxides are difficult to activate and exhibit the characteristics of being difficult to polymerize. In addition, traditional anionic ring-opening polymerization (AROP) usually has functional group tolerance problems. As such, it is of great significance to develop efficient catalytic systems to achieve the polymerization of monosubstituted epoxides. In this work, a series of tetranuclear aluminum complexes [Al(R1)3(ONO)AlR2]2 (ONO = N-methyl aminodiethylate ligand) featuring the neutral AlR3 molecules coordinated to oxygen atoms on ligand framework have been synthesized and characterized. These complexes can efficiently catalyze cyclohexene oxide (CHO) polymerization through the synergistic effect between aluminum metals, and the iso-butyl substituted tetra-aluminum complex [Al(iBu)3(ONO)Al(iBu)]2 shows the highest reactivity (TOF of 3792 h–1) at 30 °C. Notably, this tetranuclear catalyst demonstrates exceptional catalytic activity in the polymerization of monosubstituted epoxide substrates. Mechanistic investigations elucidate the distinct roles of the aluminum centers in the synergistic catalytic systems for the first time: the neutral AlR3 moiety serves as the initiator for ROP, whereas the Al–R group functions as a Lewis acidic activator that facilitates epoxide monomer activation. This study provides important guidance for the controlled synthesis of polyether architectures from monosubstituted epoxide precursors.
Supporting Information
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Appendix S1: Supporting Information |
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