エナチオセレクティブのブロンステッド塩基触媒は,キラルサイクロプロペニミネスによる
Jeffrey S Bandar1, Tristan H Lambert
1Department of Chemistry, Columbia University, New York, New York 10027, United States.
Journal of the American Chemical Society
|March 16, 2012
まとめ
チラル・サイクロプロペニミンは,ミカエル反応の有効なエナチオセレクティブ・ブロンステッド塩基触媒である. この研究は,その準備的なスケール合成と応用を実証し,非対称な触媒のための新しいツールを提供します.
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
背景:
- チラル・ブロンステッド塩基は,エナチオセレクティブ合成に不可欠である.
- サイクロプロペニミンは,新しい有機塩基のクラスである.
研究 の 目的:
- キラル・サイクロプロペニミンを高効率のエナチオセレクティブ・ブロンステッド塩基触媒として導入する.
- 非対称なマイケル反応におけるこれらの触媒の有用性を実証するために.
- 触媒のスケーラブルな合成を提供し,その性質を調査する.
主な方法:
- エナチオセレクティブ マイケル反応は,キラルな2,3-ビス (dialkylamino) サイクロプロペニミン触媒を使用しています.
- 催化剤と製品の製剤スケール合成.
- サイクロプロペニミンの基本性測定.
- 陽子化された触媒のX線結晶学.
主要な成果:
- グリシンイミン基板のマイケルの反応で達成された高いエナンチオセレクティブ性.
- 25gスケールの準備反応の実証.
- 最適な触媒のスケーラブル合成が報告されました.
- 2,3-bis(dialkylamino) サイクロプロペニミンの基本性は,フォスファゼン基と比較できると判明しました.
- X線結晶構造とメカニズムの論理的根拠が提供されています.
結論:
- チラルのサイクロプロペニミンは,エナチオセレクティブのブロンステッド塩基触媒の強力な新クラスです.
- これらの触媒は,迅速で高度にエナチオセレクティブなマイケルの反応を促進します.
- この発見は,触媒反応の提案されたメカニズムとステレオ化学的結果を支持する.
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