新種のビス (phosphine) モノキシドキラルリガンドを用いたアルファキラルアミンの非対称的,触媒的合成
Alessandro A Boezio1, Julien Pytkowicz, Alexandre Côté
1Département de Chimie, Université de Montréal, P.O. Box 6128, Station Downtown, Montréal (Québec), Canada H3C 3J7.
Journal of the American Chemical Society
|November 20, 2003
まとめ
新しいリガンドであるBozPHOSは,N-フォスフィノイリミンとダイアルキルジンク反応剤からアルファキラルアミンの効率的な銅触媒合成を可能にします. この方法は,低触媒負荷を用いて,反応性の低いジメチル亜鉛でも,高い収量とエナチオ選択性を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- アシンメトリック・カタリシス
- 有機金属化学 有機金属化学
背景:
- キラルアミンは,医薬品や農薬の重要な構成要素です.
- エナティオメリックに純粋なアミンを合成するための効率的な触媒的方法は非常に求められています.
- イミンへの銅触媒添加は,キラルアミンへの有望な経路を表しています.
研究 の 目的:
- 銅触媒による非対称的加法反応のための新しい,高度に効果的なリガンドを開発する.
- アルファキラルアミンの合成における新しいリガンドであるBozPHOSの有用性を実証する.
- ディメチル亜鉛のような挑戦的な基板とのリガンドの性能を調査する.
主な方法:
- N-フォスフィノイリミンにダイアルキルジンク反応剤の銅触媒添加.
- 新しく開発されたフォスフィン一酸化物リガンドであるMe-DuPHOS一酸化物 (BozPHOS) を利用した.
- 反応条件のスクリーニングにより,収量,エナチオセレクティブ性,および触媒負荷を最適化します.
主要な成果:
- BozPHOSは,銅触媒反応のリガンドとして高い有効性を示しました.
- アルファキラルアミンの高い収量と優れたエナチオ選択性 (ee) を達成した.
- このプロセスは,反応性が低いジメチル亜鉛でも効果的でした.
- 低触媒負荷 (3mol %) は,高い製品形成に十分であった.
結論:
- Me-DuPHOS一酸化物 (BozPHOS) は,アルファキラルアミンの銅触媒による非対称合成のための非常に効果的なリガンドです.
- この方法論は,価値あるキラルアミンの構成要素への堅牢で効率的な経路を提供します.
- 開発されたプロセスは,高収量,広範囲の基板範囲,低触媒負荷での優れたエナチオセレクティブ性を含む重要な利点を提供しています.
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