エナチオセレクティブ・プロトネーション反応のためのブロンステッド酸触媒
Cheol Hong Cheon1, Hisashi Yamamoto
1Department of Chemistry, University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, USA.
Journal of the American Chemical Society
|June 28, 2008
まとめ
金属のないエナチオセレクティブプロトネーションのために,新しいキラルブロンステッド酸触媒が開発されました. この触媒は,低負荷でも,高い選択性を持つシリルエノールエーテルを効率的にプロトン化します.
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:
- チラル・ブロンステッド酸は,非対称合成における重要な触媒である.
- 金属のない触媒の開発は,グリーン化学の重要な目標です.
- エナチオセレクティブ・プロトネーションは,キラル分子を作るための基本的な変換です.
研究 の 目的:
- 新しく,高度に反応性があり,頑丈なキラル型ブロンステッド酸触媒の開発.
- シリルエノールエーサーのエナチオセレクティブプロトネーションを触媒化した最初の金属のないブロンステッド酸を実証する.
- 低負荷で触媒の効率を調査する.
主な方法:
- キラルなN-トリフリルチオフォスフォラミド触媒の合成.
- シリルエノールエーサーのエナチオセレクティブプロトネーションにおける触媒の適用.
- 反応条件と触媒の負荷の最適化.
主要な成果:
- 非常に反応性があり頑丈なキラルなN-トリフリルチオフォスフォラミド触媒が成功裏に開発されました.
- 触媒は,シリルエノールエーテルの最初の金属のないブロンステッド酸で触媒化されたエナチオセレクティブプロトネーションを可能にしました.
- 高いエナチオセレクティビティは,0.05 mol %という低い触媒負荷でも達成されました.
結論:
- チラルN-トリフリルチオフォスフォラミドは,金属フリーエナンチオセレクティブプロトネーションの効果的な触媒である.
- この方法論は,キラル化合物へのグリーンで効率的な経路を提供します.
- 触媒の低負荷要求は,その実用的な適用性を高めます.
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