内部アルキンのコバルト触媒による非対称配列水解/水素化
Jun Guo1, Biao Cheng1, Xuzhong Shen1
1Department of Chemistry, Zhejiang University , Hangzhou 310058, China.
Journal of the American Chemical Society
|October 19, 2017
まとめ
新しいコバルト触媒法により,内部のアルキンからキラル・オルガノボロナートの単体合成が可能である. この効率的なプロセスは,高度に地域とエナチオセレクティブの水溶解と水素化のための新しいキラルリガンドを使用します.
科学分野:
- 有機金属化学
- 非対称な触媒
- 合成有機化学
背景:
- チラルのオルガノボロナートは有価な合成中間物質である.
- 合成のための効率的な触媒的方法の開発は依然として課題です.
研究 の 目的:
- キラル二次オルガノボロナートを合成するための新しい,高度に地域とエナチオセレクティブのワンポット方法を開発する.
- コバルト触媒変換のための新しいキラルイミダゾリンイミノピリジン (IIP) リガンドを導入する.
主な方法:
- HBpinを用いた内部アルキンの1ポット連続水酸化/水酸化.
- 新しいキラルイミダゾリンイミノピリジン (IIP) リガンドと調整されたコバルト触媒を使用します.
- 水素化ステップに水素気球を使用する.
主要な成果:
- 内部アルキンがキラルなオルガノボロナートに変換する際に高い地域選択性とエナチオ選択性を達成した.
- 素早く入手可能な原料で機能的なグループ耐性を証明した.
- 価値あるキラル二次オルガノボロナートを 合成した
結論:
- 開発されたコバルト触媒プロトコルは,キラル・オルガノボロナートへのアクセスのための効率的で新しい戦略を提供します.
- 新しいキラルIIPリガンドは,高いステレオ制御で水酸化と水素化のステップの両方を促進するのに有効です.
- 機械学的な研究は,水素化の経路に続く連続的な水素化を示唆する.
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