シリルケテンイミンの触媒的非対称プロトネーション
Joyram Guin1, Georgy Varseev, Benjamin List
1Max-Planck-Institut für Kohlenforschung, Kaiser Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
Journal of the American Chemical Society
|February 1, 2013
まとめ
キラルリン酸は,シリルケテンイミンのエナチオセレクティブ・プロトネーションを触媒化する. この効率的な方法は,メタノールを使用してラセミック基板を価値あるエナチオンの濃縮ニトリルに変換します.
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
背景:
- シリルケテンイミンは,多用途の合成中間物質です.
- ニトリルのエナチオセレクティブ合成は,有機化学における重要な課題である.
研究 の 目的:
- シリルケテンイミンのエナチオセレクティブプロトネーションのための効率的な触媒的方法を開発する.
- 簡単に入手可能なラセミック前駆体から,高度にエナンチオ濃縮されたニトリルにアクセスするために.
主な方法:
- キラルリン酸 (TRIPまたはSTRIP) を使用した触媒的非対称プロトネーション.
- プロトン源とシリル受容体としてメタノールを利用した.
- 様々な置換されたラセミックシリルケテンイミンの反応範囲を調査した.
主要な成果:
- プロトネーション反応で高い触媒効率とエナチオセレクティビティが得られる.
- 置換されたシリルケテンイミンの範囲を相応のニトリルに変換することに成功しました.
- 高いエナティオメール過量 (ee) を有する得られた製品.
結論:
- 開発されたプロトコルは,エナチオ濃縮ニトリルへの新しい効果的な経路を提供します.
- キラルリン酸触媒は,非対称なプロトネーション反応のための強力な戦略を提供します.
- この方法は,シリルケテンイミンの合成的有用性を,エナンチオセレクティブ変換で拡大します.
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