アレネスのダイナミック・キネティック・アシンメトリック・アリル・アルキル化
Barry M Trost1, Daniel R Fandrick, Diana C Dinh
1Department of Chemistry, Stanford University, Stanford, CA 94305-5080, USA. bmtrost@stanford.edu
Journal of the American Chemical Society
|October 13, 2005
まとめ
この研究は,ダイナミックな動的非対称性アリルアルキル化を用いたキラルアルレンの生成のための新しい方法を示しています. この反応は独特の塩基依存性を示し,価値あるキラル構成要素へのアクセスを可能にします.
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:
- エナチオメリックに純粋なアレンへのアクセスは,複雑な分子を合成するために不可欠です.
- アレンの非対称性アリルアルキル化のための以前の方法には,限界があります.
研究 の 目的:
- ラセミアルレンアセテートの新しいダイナミック・キネティック・アシンメトリック・アリル・アルキレーションを開発する.
- 異なる塩基がエナチオ選択性に及ぼす影響を調査する.
主な方法:
- DACH-フェニルトロストリガンドを非対称な触媒に利用した.
- アルキル化反応では,マロナートおよびアミンヌクレオフィルを使用した.
- 製品のRh(I) 触媒化された分子内 [4 + 2] サイクル添加を行った.
主要な成果:
- 様々なキラルアレンに対して高いエナティオメール過量 (84~95%) を達成した.
- 核愛型の両方の塩基に対するエナンチオセレクティブ性の異常な依存性を発見した.
- 複数のステレオセンターに軸性キラリティを成功裏に転送し,オレフィン幾何学を制御しました.
結論:
- 開発された方法は,高度にエナチオメリックに濃縮されたアレンに一般的アクセスを提供します.
- 塩基依存のエナチオセレクティビティは,非対称な誘導機構に関する新しい洞察を提供します.
- その後のサイクロアディションは,複雑な分子合成におけるキラルアレンの有用性を示しています.
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