N-メチルとN-アルキルイミンの直接非対称な水素化は,Ir (III) H触媒を用いる
Ernest Salomó1, Albert Gallen2, Giuseppe Sciortino3,4
1Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology , Baldiri Reixac 10 , 08028 Barcelona , Spain.
Journal of the American Chemical Society
|November 27, 2018
まとめ
この研究では,イミンの非対称的水素化のための新しいイリジウム触媒を導入し,初めて高いエナチオ選択性を達成しました. カタリスト
科学分野:
- 有機金属化学
- 非対称な触媒
- 合成有機化学
背景:
- イミンの直接非対称化水素化は有機合成における重要な変換である.
- 効率的で選択的な触媒システムの開発は依然として大きな課題です.
- イリジウム複合体は,そのユニークな反応性のために,水素化反応のためにますます探索されています.
研究 の 目的:
- N-メチルとN-アルキルイミンの直接非対称な水素化のための新しいカチオンイリジウム触媒を開発する.
- これまでに報告されていないこの変異において高いエナンチオセレクティブ性を達成する.
- 触媒の構造と反応条件が触媒性能に与える影響を調査する.
主な方法:
- P-ステロゲン MaxPHOX リガンドを含む新しいカチオンイリジウム複合体の合成.
- 様々なN-メチルおよびN-アルキルイミンの直接非対称水素化における触媒の適用
- 反応機構とステレオ化学的結果を合理化するために,密度関数理論 (DFT) の計算を使用した.
主要な成果:
- 開発された触媒システムは,イミンの非対称な水素化のために高いエナチオ選択性 (最大94%) を達成した.
- これは,この基板クラスのこのような高いエナチオ選択性を報告する最初の触媒システムです.
- ラビルテトラヒドロフーラン (THF) リガンドは低温でも効果的な触媒活性化と高反応性を促進しました.
結論:
- イミンの水素化のための新しい,高度にエナチオセレクティブな触媒系が成功裏に開発されました.
- P-ステレオジェニックのMaxPHOXリガンドは,高いステレオコントロールを達成する上で重要な役割を果たします.
- DFT計算は,反応のステレオ化学的経路に関する貴重な洞察を提供し,将来の触媒設計に役立ちます.
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