単純なアルファ,ベータ不飽和ケトンによる最初の一般的エナンチオセレクティブ触媒ダイエルス・アルダー反応
Alan B Northrup1, David W C MacMillan
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
Journal of the American Chemical Society
|March 14, 2002
まとめ
研究者らは,単純なケトンを用いたエナチオセレクティブのダイエルス・アルダー反応のための新しいイミニウム触媒法を開発しました. この有機触媒的アプローチは,以前は高度なステレオ制御で困難なサイクル添加にアクセスを提供します.
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:
- ディエルス・アルダー反応は,有機合成における基本的な [4 + 2] サイクル添加である.
- エナチオセレクティブ触媒は,キラル分子の合成に不可欠である.
- 単純なケトンデオノフィルは,エナンチオセレクティブのダイエルス・アルダー反応で用いることが困難でした.
研究 の 目的:
- 単純なケトンデオノフィルを用いたダイエルス・アルダー反応のための最初の一般的なエナンチオセレクティブ触媒的アプローチを開発する.
- ダイエルス・アルダー反応の変種へのエナンチオセレクティブアクセスを可能にするために,以前はキラルルイス酸触媒でアクセスできなかった.
主な方法:
- イミニウム触媒のための新しいキラルアミン触媒の開発.
- 触媒を様々な周期性および非周期性ケトンおよびダイエンの [4 + 2] サイクル添加で適用する.
- 計算モデリングを使用して,観察されたエナンチオインダクションを理解します.
主要な成果:
- 単純なケトンダイノフィールによるディエルス・アルダー反応のエナチオセレクティブ触媒の成功.
- 触媒が幅広いサイクルおよび非サイクルケトンおよびダイエンの基板を収納する能力を実証した.
- サイクル添加反応で高いレベルのエナンチオ誘導が得られた.
結論:
- 新しい有機触媒イミニウム触媒法により,単純なケトンによるエナンチオセレクティブのダイエルス・アルダー反応に対する一般的なアプローチが提供されています.
- この方法は,エナチオセレクティブのダイエルス-アルダーサイクル添加の範囲を拡大します.
- 開発された触媒とコンピューティングモデルは,非対称合成の重要な進歩を提供します.
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