効率的なZ-選択的オレフィン-アクリラミドクロスメタテシスは,ステリカルに要求されるサイクロメタル化ルテニウム触媒によって可能
Yan Xu1, Jonathan J Wong2, Adrian E Samkian1
1Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
Journal of the American Chemical Society
|December 4, 2020
まとめ
新しいルテニウム触媒は,アクリラミドの効率的なZ選択的交叉メタテシスを可能にし,シス-マイケルの受容体を生成します. この突破は 簡単に手に入る素材を使って 簡素化された合成の経路を提供します
科学分野:
- 有機化学
- カタリシス
- 材料科学
背景:
- 交差転移反応はC−C結合形成に不可欠である.
- 選択的で効率的な触媒システムの開発は依然として大きな課題です.
- アクリラミドは万能な構成要素ですが,その交叉転移はしばしば困難です.
研究 の 目的:
- アクリラミドと末端オレフィンのための効率的なZ選択クロスメタテシスプロトコルを開発する.
- この変換で高い反応性とステレオ選択性を達成します.
- シス-マイケルの受容体の 簡潔な合成を提供するために
主な方法:
- 大量のN-ヘテロサイクリックカルベン (NHC) リガンドを含む新しいサイクロメタラテッドルテニウム触媒を使用した.
- クロスメタテシスに対する運動的好みを促進するために,ピヴァラートアニオンリガンドを使用した.
- 反応メカニズムを解明するために,密度関数理論 (DFT) の計算を行った.
主要な成果:
- アクリラミドと末端オレフィンの交叉メタテシスで前例のないZ選択性を達成した.
- 既存の方法と比較して優れた反応性とステレオ選択性を示した.
- シンプルな材料から 価値あるシス・マイケルの受容体を作製しました
結論:
- 開発されたルテニウム催化クロスメタテシスは,シス-マイケルの受容体への効率的で選択的な経路を提供します.
- 大量のNHCリガンドとピヴァラートリガンドの使用は,反応の成功の鍵です.
- DFT計算は,触媒サイクルと選択性を決定するステップの洞察を提供します.
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