銅で触媒化された,アルキルボランによるエナチオセレクティブ・アリリック置換
Yoshinori Shido1, Mika Yoshida, Masahito Tanabe
1Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Japan.
Journal of the American Chemical Society
|October 31, 2012
まとめ
この研究は,アルキルボロン化合物を用いた最初の触媒的エナンチオセレクティブアリル代替を導入しています. この新しい方法は,機能化されたアルキル基を持つキラルアルケンを効率的に生成し,非対称合成を促進します.
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・シンセシス
- 有機金属化学 有機金属化学
背景:
- アリル基置換反応は,有機合成において根本的な役割を果たします.
- キラル・センターの形成のためのエナチオセレクティブ・メソッドの開発は極めて重要です.
- アルキルボロン化合物は独特の反応性を有していますが,エナチオセレクティブのアリル代用では十分に研究されていません.
研究 の 目的:
- アルキルボロン化合物を使った最初の触媒的エナンチオセレクティブアルリル置換反応を達成するために.
- 端末アルケンを合成するためのプロトコルを開発し,そのステレオゲンな中心部に sp(3) -アルキル基を分岐させた.
- キラルアルリシランのエナチオセレクティブ合成のための効率的な戦略を確立する.
主な方法:
- アルキル-9-BBN反応剤と原発アリル塩化物を使用した.
- コパー (I) -DTBM-SEGPHOSの触媒システムを採用しました.
- γ-シリコン置換アルリル塩化物による反応を調査した.
主要な成果:
- アリル置換で優れた γ-選択性と高いエナチオ選択性を達成した.
- 機能化されたsp ((3) -アルキル基を持つアリル型ステレオゲンな中心を特徴とする末端アルケンを成功裏に生産した.
- α-ステロゲン性キラルアリシルサイランのエナンチオセレクティブ合成のための効率的な戦略を示した.
結論:
- 開発された触媒系は,アルキルボロン反応剤によるエナンチオセレクティブ・アリル代用における画期的な進歩を表しています.
- このプロトコルは,価値あるキラル・ビルディング・ブロックへの汎用的な経路を提供します.
- この発見は,高度なステレオ化学的制御を持つ複雑な有機分子を合成するための新しい道を開く.
関連する概念動画
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