イリジウム触媒Z-選択的非対称性アリル置換反応によるZ/E運動解像度
Yi-Ming Hou1, Ru Jiang1, Jiandong Liu1
1New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China.
Journal of the American Chemical Society
|June 10, 2025
まとめ
この研究では,Z/E混合物からキラルZ-オレフィンを作るためのIr-触媒化された方法が紹介されています. 運動解像度と光誘発性異体化を利用し,Z-オレフィン合成に挑戦するために高収量とエナチオ選択性を達成します.
科学分野:
- 有機合成
- 非対称な触媒
- ステレオ選択反応
背景:
- チラルZオレフィンは,E同位体と比較して熱力学的不安定性のために合成的に困難です.
- 簡単に手に入るEオルフェンを高度なキラルZオルフェンに変換するには,エネルギー上の障壁を克服する必要があります.
- Z-olefinとE-olefinの反応性を区別することは,選択的合成には極めて重要であるが,分子触媒では困難である.
研究 の 目的:
- キラルZオレフィン合成のためのZ選択的非対称性アリル置換法を開発する.
- 効率的なZ-オレフィン生産のためにZ/Eオレフィン混合物の運動解像度を利用する.
- イソメリゼーションによるE-オレフィン前駆体からのキラルZ-オレフィンへのアクセスを可能にします.
主な方法:
- イリジウム触媒による非対称性アリル置換反応が採用された.
- オキシンドールは,Z/Eアリル炭酸混合物の運動解像度において,ヌクレオフィルとして使用された.
- 光誘導によるオレフィンE/ Zイソメリゼーションは,触媒反応と併用された.
主要な成果:
- 反応は,より速い酸化添加と核愛性の攻撃により,E対位のZ-アリルカルボネートに対してより高い反応性を示した.
- 高い収穫率 (最大97%) とエナチオ選択性 (96% ee) が達成されました.
- 優れたZ/ E比率 (>19: 1) が得られ,効果的な運動解像度と異体化が示されました.
結論:
- この研究は,非対称なツジ・トロスト型反応において前例のないアプローチを示している.
- 先進的なキラルZ-オレフィン合成のためのユニークな戦略が確立されています.
- この方法は,熱力学的に不利なZ-オレフィンを入手可能な前駆体から実現可能な経路を提供します.
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