Chiral Mn
| Autor: | Cun Wang, Yue Wang, Kaiyun Shi, Fu Xiangkai, Wang Zhongming, Dongwei Li, Xiaochuan Zou |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Materials science
Polymers and Plastics Chiral MnIII (salen) complex covalent attachment chemistry.chemical_element Homogeneous catalysis 010402 general chemistry Heterogeneous catalysis 01 natural sciences Article Catalysis lcsh:QD241-441 chemistry.chemical_compound lcsh:Organic chemistry Polymer chemistry Organic chemistry Indene Zirconium 010405 organic chemistry Enantioselective synthesis heterogeneous catalyst General Chemistry hybrid zirconium phosphonate asymmetric epoxidation Phosphonate 0104 chemical sciences chemistry Covalent bond |
| Zdroj: | Polymers, Vol 9, Iss 3, p 108 (2017) Polymers Polymers; Volume 9; Issue 3; Pages: 108 |
| ISSN: | 2073-4360 |
| Popis: | Chiral MnIII (salen) complex supported on modified ZPS-PVPA (zirconium poly(styrene-phenylvinylphosphonate)) and ZPS-IPPA (zirconium poly(styrene-isopropenyl phosphonate)) were prepared using ⁻CH₂Cl as a reactive surface modifier by a covalent grafting method. The supported catalysts showed higher chiral induction (ee: 72%⁻83%) compared with the corresponding homogeneous catalyst (ee: 54%) for asymmetric epoxidation of α-methylstrene in the presence of 4-phenylpyridine N-oxide (PPNO) as axial base using NaClO as an oxidant. ZPS-PVPA-based catalyst 1, with a larger pore diameter and surface area, was found to be more active than ZPS-IPPA-based catalyst 2. In addition, bulkier alkene-like indene, was efficiently epoxidized with these supported catalysts (ee: 96%⁻99%), the results were much higher than those for the homogeneous system (ee: 65%). Moreover, the prepared catalysts were relatively stable and can be recycled at least eight times without significant loss of activity and enantioselectivity. |
| Databáze: | OpenAIRE |
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