サイズ選択性アルケンのメタテシスのためのマクロサイクルルテニウムカルベン
Yutong Zhang1, Steven T Diver1
1Department of Chemistry , University at Buffalo, the State University of New York , Amherst , New York 14260-3000 , United States.
Journal of the American Chemical Society
|February 20, 2020
まとめ
新しいマクロサイクルルテニウムカルベンの触媒は,選択的なクロスアルケンの転移を可能にします. その反応性はアルケンの大きさによって変化し,複雑な反応で分化と選択的産物形成を可能にします.
科学分野:
- 有機金属化学
- カタリシス
- 有機合成
背景:
- アルケンの転移は,強力な炭素-炭素結合形成反応である.
- 交差メタテシスのための選択的触媒の開発は,有機合成における重要な課題です.
- マクロサイクルのリガンドは,触媒の反応性と選択性に影響を与える.
研究 の 目的:
- 新しいマクロサイクルルテニウムカルベンの触媒を合成し,特徴づけること.
- ホモディメリゼーションとクロスメタテシス反応における触媒の反応性を調査する.
- ステリック因子に基づいて選択的なアルケンの分化を達成する触媒の能力を実証する.
主な方法:
- マクロサイクルルテニウムカルベンの合成
- 各種の1型アルケンのホモディメリゼーションにおける触媒性能の評価
- 異なるアルケンを含む競争交差メタテシス反応における触媒の試験.
- 選択性および基板範囲を決定するための反応結果の分析.
主要な成果:
- 合成されたマクロサイクリックRu触媒は,同型化における異なる1型アルケーンに対する明確な反応性を示す.
- ホモディメリゼーションにおける反応性は,アリル置換物の総量と相関する.
- 触媒は,ターチルブチルアクリlateのようなステリカル分化アルケンの間の交叉メタテシス反応において高い選択性を示しています.
- 2つの準備例は,選択的なクロスメタテシスにおける触媒の有用性を示しています.
結論:
- マクロサイクルの設計は,アルケンの転移のためのRuカルベンの触媒にユニークな反応性と選択性を与える.
- アルケンをサイズによって区別する触媒の能力は,選択的なクロスメタテシスを達成する鍵です.
- この研究は,選択的アルケンの転化による制御された合成のための新しいツールを提供します.
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