非対称な触媒における高度な協調性の基板の管理:ランタンベースの三重触媒による触媒的非対称アミネーション
Tomoyuki Mashiko1, Naoya Kumagai, Masakatsu Shibasaki
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Journal of the American Chemical Society
|September 30, 2009
まとめ
新型ランタン/アミド触媒は,サクシニミドやアルファ-アルコキシカルボニルアミドなどの難題となる基質の非対称なアミネーションを可能にし,高収量とエナチオセレクティブ性を有する. この画期的な発見は,非対称な触媒の新たな可能性を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- アシンメトリック・シンセシス
背景:
- 触媒的非対称アミネーションは,キラル分子の合成に不可欠である.
- 挑戦的な基板のための効率的な触媒の開発は,有機合成の重要な目標です.
研究 の 目的:
- 非対称アミネーションのための新しいランタン/アミドベースの触媒システムを開発する.
- 挑戦的な基板の触媒性能とメカニズムを調査する.
主な方法:
- ランタニウム窒素六水素 (R) -3aとH-d-Val-O(t) Buを触媒システムとして使用した.
- 機械学的調査のために,光譜分析,制御実験,運動学的研究を行いました.
- サクシニミド誘導体とN-非置換アルファ-アルコキシカルボニルアミドの非対称アミネーションに触媒を適用した.
主要な成果:
- 保護されていないサクシニミド誘導体1の触媒非対称アミネーションが,触媒負荷1mol%で達成された.
- 前例のないN-非置換アルファ-アルコキシカルボニルアミドに対する有効性が実証され,最大99%の収量と99%以上のエナティオメール過剰 (ee) を有する製品が得られる.
- 可能性の高い活性種として,La(NO(3))(3)*6H(2)O/(R)-3a/H-d-Val-O(t) Buを含む三元複合体を特定しました.
結論:
- ランタン/アミド触媒システムは,高い触媒性能とエナチオコントロールを備えています.
- ランタン調整による基板活性化と,移行状態における協力的な水素結合は,反応の成功の鍵となる.
- この方法により,非対称アミネーションの適用範囲は,以前アクセス不可能な基板に拡大されます.
さらに関連する動画
関連する概念動画
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