熱力学的な制御下でアトロピソメアの非対称合成のためのリチウム-硫黄酸化-リチウム交換
Jonathan Clayden1, David Mitjans, Latifa H Youssef
1Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK. j.p.clayden@man.ac.uk
Journal of the American Chemical Society
|May 9, 2002
まとめ
この研究では,エナチオメリックに純粋な芳香性アミドを生成するための新しいダイナミック解像度法が導入されています. このプロセスは,硫黄酸化基を用いて形状を制御し,有価なアトロピソメア化合物の効率的な合成を可能にします.
科学分野:
- 有機化学 オーガニック・ケミストリー
- ステレオ化学 ステレオ化学
- 合成方法論 合成方法論
背景:
- アロマティックアミドは,ステレオジェニックなAr-CO軸を持っています.
- アロマティックアミドにおけるアトロピソメリズムを制御することは困難です.
- 既存の方法には,効率性と反選択性が欠けている.
研究 の 目的:
- アロマティックアミドのダイナミック解像度のための新しい方法を開発する.
- 高度にエナチオメリックに富んだアトロピソメリック三次芳香胺を合成する.
- 硫酸化物置換剤を用いた強力な構成バイアスを導入する.
主な方法:
- アロマティックアミドのオーソリチ化.
- (-) -メンチルp-トルーエネスルフィネートとの反応により,硫酸化物を導入する.
- t-BuLiを用いた硫酸化物-リチウム交換.
- 再生されたオルガノリチウムを電子性で捕まえる.
主要な成果:
- 硫酸化物置換剤は,強い形状的バイアスを誘導する.
- 急速な均衡は,単一に定着した二重同位体であるAr-COアトロピゾーマーにつながります.
- エナティオメリックに純粋で,形状的に安定したオートホリチ化アミドが再生されます.
- エレクトロフィリック・トラッピングにより,高度にエナティオメリックに濃縮されたアトロピソメリック・アミドが得られます.
結論:
- 記述された方法は,熱力学的な制御下でダイナミックな解像度を達成します.
- この戦略は,エナチオメリックに純粋なアトロピソメリック三次アロマティックアミドへの効率的なアクセスを提供します.
- リチウムを硫黄酸化物とリチウムに戻すという一時的な置換は,このプロセスの鍵です.
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