アルキンによるRh触媒によるC-H無効化によるアゾニアヘリケンのエナンチオセレクティブ合成
Qiang Wang1, Wen-Wen Zhang2, Chao Zheng1
1State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China.
Journal of the American Chemical Society
|December 28, 2020
まとめ
新しいロジウム (III) 触媒法により,エナチオセレクティブのC-H活性化および無効化反応が可能である. このプロセスは,イソキノリン誘導体とアルキンを基調に合成し,高収量とエナチオ選択性を有する.
科学分野:
- 有機金属化学
- 非対称な触媒
- 有機合成
背景:
- チラルのアゾニアヘリケンは,超分子化学と材料科学における重要な構造モチーフである.
- これらの複雑な分子への効率的でエナチオセレクティブな合成経路の開発は依然として大きな課題です.
研究 の 目的:
- 新しいロジウム (III) 触媒によるC-H活性化/無効化戦略を開発する.
- ヒラルアゾニアヘリケンを合成する.
主な方法:
- 触媒の前駆体としてキラルCpRh (III) コンプレックスを使用した.
- キラル酸を共催剤として使った.
- 1-アリルイソキノリン誘導体と様々なアルキンの間の直接無効反応を調査した.
主要な成果:
- 多様なキラルアゾニアヘリケンの合成を達成した.
- 優れた収穫率 (最大99%) と高いエナチオ選択性 (最大96% ee) が得られた.
- 機理学的な調査は,C-Hボンドの割れが潜在的に売上を制限するステップであることを示しました.
結論:
- 開発されたロジウム (III) 触媒化されたプロセスは,エナチオメリックに濃縮されたアゾニアヘリケンのための効率的な経路を提供します.
- この方法論は複雑なキラル・ヘリクル構造を 構築するための貴重なツールである.
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