2019 Fiscal Year Final Research Report
Development of Highly Active Transition Metal Catalysts Based on Solid Support Strategies
| Project Area | Precise Formation of a Catalyst Having a Specified Field for Use in Extremely Difficult Substrate Conversion Reactions |
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| Project/Area Number |
15H05801
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| Research Category |
Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
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| Allocation Type | Single-year Grants |
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| Review Section |
Science and Engineering
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| Research Institution | Hokkaido University |
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Principal Investigator |
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| Project Period (FY) |
2015-06-29 – 2020-03-31
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| Keywords | 触媒設計 / ホスフィン / ポリスチレン / 固相担持 / 架橋剤 / ニッケル / アミノ化 / クロスカップリング |
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| Outline of Final Research Achievements |
Polystyrene(PS)-supported phosphines are widely used for heterogeneous metal catalysis. The phosphine moieties have generally significant mobility even in cross-linked PS resins, and hence exhibit ligand properties similar to those of their homogeneous counterparts. In many cases, however, the polymer chain causes unfavorable steric effects, resulting in reduced catalyst efficiency. We prepared a new type of PS-phosphine hybrid (PS-DPPBz) through radical emulsion copolymerization of styrene monomers in the presence of tetravinylated 1,2-bis(diphenylphosphino)benzene. PS-DPPBz exhibited good swelling properties with aprotic organic solvents.
As a conceptual advance of our studies with solid-immobilized ligand toward enantioselective reactions, we showed that the BINOL-based monodentate phosphite chiral ligand enabled the highly enantioselective Ir-catalyzed directed borylation of unactivated methylene C(sp3)-H bonds in saturated hydrocarbon frameworks of substituted heteroarenes.
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| Free Research Field |
有機金属化学
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| Academic Significance and Societal Importance of the Research Achievements |
分離・再利用が容易な高分子固定化金属触媒による合成プロセスの効率化が期待される。しかし、高分子鎖の立体障害によって触媒活性がしばしば低下する。我々は、複数の重合部位を有するホスフィンを高分子架橋剤とすることで金属配位点を空間的に孤立化させて高活性金属種を生成する手法を開発した。単座ホスフィンを３点架橋剤として得られるPS-TPPや２座ホスフィンを４点架橋剤とするPS-DPPBzが代表例である。
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