ヘテロアリル誘導型エノリゼーション-デカルボキシル配列によるイリジウム誘導型エナチオセレクティブアルケンの水酸化
Changcheng Jing1, Wenbin Mao1, John F Bower1
1Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, United Kingdom.
Journal of the American Chemical Society
|October 25, 2023
まとめ
この研究は新しいエナチオセレクティブ・デカルボキシラティブ・クロスカップリング法を導入する. オレフィンの効率的な水酸化のためにキラルイリジウム複合体を使用し,高い選択性を持つ有価なアルキル化ヘテロアレンを生成します.
科学分野:
- 有機金属化学
- 非対称な触媒
- 合成有機化学
背景:
- 水酸化反応はC−C結合形成に不可欠である.
- 枝分かれした水アルキル化において高いエナチオ選択性を達成することは依然として課題です.
- 脱炭素化クロスカップリングは原子経済的な合成経路を提供します.
研究 の 目的:
- オレフィンに対する新しいエナンチオセレクティブ・水酸化法を開発する.
- ヘテロアリルターチブチルアセテートをカップリングパートナーとして使用する.
- 定義されたステレオセンターを持つアルキル化ヘテロアレンを合成する.
主な方法:
- キラル・ディフォスフィン・リガンド (DuanPhos) を含むイリジウム (Iridium) コンプレックスを使用する.
- ヘテロアリルテルブチルアセテートと反応するスタイレンとα-オレフィン.
- 初期アダクトのインサイト酸促進デカルボキシル化
主要な成果:
- 水素アルキル化で観察された完全な分岐選択性.
- 非常に高いエナチオ選択性が得られた.
- 定義されたβステレオセンターを持つアルキル化ヘテロアレンの形成.
- 反応はステレオ定義のキラルイリジウムエノラート中間体によって進行する.
結論:
- 開発された方法は,C ((sp3) -C ((sp3)) のエナチオセレクティブ・デカルボキシラティブ・クロスカップリングを表しています.
- このアプローチは,エナティオメリックに濃縮されたアルキル化ヘテロアレンへの効率的なアクセスを提供します.
- このメカニズムには,指向されたエノライゼーションとキラルイリジウムエノラート経路が含まれています.
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