非対称な触媒におけるキラルアレンを含むフォスフィン
Feng Cai1, Xiaotao Pu, Xiangbing Qi
1Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75398-9038, United States.
Journal of the American Chemical Society
|October 7, 2011
まとめ
塩基群を持つキラルアレンは,移行金属のリガンドとして作用する. Rhodium ((I)) とのアレン・ビスフォシン・リガンドにより,α-ケトエステルにアリルボロン酸を高度にエナンチオセレクティブに添加することができる.
科学分野:
- 有機金属化学 有機金属化学
- アシンメトリック・カタリシス
背景:
- アレネス,特にキラル1,2-ディエネスは,多用途の有機分子です.
- 新種のリガンドの開発は,移行金属触媒の進歩に不可欠です.
研究 の 目的:
- 基本的機能を持つアレンが付加され,移行金属の効果的なリガンドとして機能することを実証する.
- 非対称な触媒のためのアレンを含むビスホスフィンリガンドを開発し,利用する.
主な方法:
- アレンを含むビスホスフィンリガンドの合成.
- ロジウム ((I) コンプレックスへのリガンドの調整.
- アリルボロン酸をα-ケトエステルに非対称的に加える際に生じる触媒の適用.
- 溶液と固体構造分析.
主要な成果:
- アレネ・ビスフォシン・リガンドは,Rh (I) への調整に成功しました.
- Rh (I) 複合体は,高いエナチオ選択性を持つα-ケトエステルにアリルボロン酸の添加を触媒化した.
- 構造分析により,アルレンの1つのオレフィンと金属の中心との協調が確認され,ビ-とトリデントリガンドが形成された.
結論:
- 基本的な機能を持つアルネは,移行金属の有効なリガンドである.
- 開発されたアレン・ビスフォシン・リガンドは,高度にエナチオセレクティブの結合添加を促すのに有効である.
- アレネリンガンドの調整モードは,新しい触媒システムを設計するための機会を提供します.
関連する概念動画
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