ルテニウム/フォスフォラミドイット触媒による非対称な中断メタロエネ反応
Barry M Trost1, Michael C Ryan1
1Department of Chemistry, Stanford University , Stanford, California 94305-5580, United States.
Journal of the American Chemical Society
|February 23, 2016
まとめ
チラルルテニウム触媒は,アリル塩化物から循環性アルコールのステレオ選択的合成を可能にします. この重要な変換において,新しいリガンドの設計により,二重選択性とエナチオ選択性の両方が強化される.
科学分野:
- 有機化学
- カタリシス
- アシンメトリック・シンセシス
背景:
- アリル塩化物は多用途の合成中間物質である.
- 循環性化合物の合成において高いステレオ選択性を達成することは依然として課題です.
研究 の 目的:
- トランス・ディスプスチューテッドの 5 つと 6 つのリングシステムを合成するための高度にダイアステロセレクティブとエナチオセレクティブの方法を開発する.
- 合成されたキラルアルコールの有用性を調査する.
主な方法:
- アリル塩化物の変換にキラルルテニウム触媒を用いた.
- 大量の3,3'-置換による新しいBINOLベースのフォスフォラミドリガンドを開発した.
- 形成されたステレオ定義の二次および三次アルコールを特徴づける.
主要な成果:
- サイクルシステムの形成において完璧なダイアステレオ選択性と高いエナチオ選択性を達成した.
- アルキルルテニウム中介物質と水捕獲によるステレオ定義アルコールの形成を特定した.
- 高い収量とステレオ選択性を持つダイアステレオ選択的フリーデル・クラフト反応で成功していることが実証されています.
結論:
- 開発されたキラルルテニウム触媒は,価値あるキラルサイクルアルコールへの効率的な経路を提供します.
- この新しいリガンドは,触媒変換において高いステレオ制御を達成するために不可欠である.
- 合成されたキラルアルコールは,さらなる非対称合成のための有用な構成要素として機能する.
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