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Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy
Published on: November 9, 2019
高度に選択的な非対称化水素化は,3つの阻害象限ビスホスフィンロジウム触媒を用いて行われます
Garrett Hoge1, He-Ping Wu, William S Kissel
1Pfizer Global Research and Development, 2800 Plymouth Road, Ann Arbor, Michigan 48105, USA. garrett.hoge@pfizer.com
Journal of the American Chemical Society
|May 13, 2004
まとめ
新しいロジウム触媒 (5) は,アミノ酸誘導体と製薬前駆物の高度にエナチオセレクティブな非対称な水素化を可能にします. この方法は,既存の触媒と比較して,大規模な合成のための利点を提供しています.
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
- 薬用化学 薬用化学について
背景:
- チラルリンガンドと金属複合体は,エナチオセレクティブ合成に不可欠である.
- ロジウム触媒は,非対称な水素化反応で広く使用されています.
- エナチオメリックに純粋な化合物の効率的な合成は,医薬品にとって不可欠です.
研究 の 目的:
- 新しいロジウム複合体の両方のエナティオメールを合成する (5).
- 非対称的水素化におけるロジウム複合体5のエナチオ選択性を評価する.
- 大規模合成のためのRh-Me-DuPhosと触媒5aの有効性を比較する.
主な方法:
- リガンド2とロジウム複合体の合成 5. ロジウム複合体の合成
- エナティオメア分離のためのキラル高性能液体染色法 (HPLC).
- アルファ-アセタミドデヒドロアミノ酸 (6a-e) とプレガバリンの前駆体 (8).
主要な成果:
- リガンド2とロジウム複合体の2つのエナティオメアの合成に成功 5. ロジウム複合体の合成に成功
- ロジウム複合体5は,水素化反応において高いエナチオ選択性 (>99% ee) を示した.
- 触媒5aは,前体8の大規模水素化においてRh-Me-DuPhosよりも優れていることが示された.
結論:
- 妨害された四角を特徴とする新しいロジウム複合体5は,優れたエナチオセレクティビティを達成します.
- この触媒は,アミノ酸誘導体および製薬前駆体の非対称な水素化に有効です.
- カタリスト5aは,工業規模の非対称水素化のための有望な代替案です.
関連する概念動画
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