電子的に活性化されたC-Hボンドの存在下での,触媒制御による非活性化C-Hボンドの選択的機能化
Wenbin Liu1, Zhi Ren1, Aaron T Bosse1
1Department of Chemistry , Emory University , 1515 Dickey Drive , Atlanta , Georgia 30322 , United States.
Journal of the American Chemical Society
|September 18, 2018
まとめ
新しいキラルディロジウム触媒は,未活性化結合の選択的C-H機能化を可能にします. この突破は,複雑な天然製品の合成でも,高い選択性と広範な適用性を提供します.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- ディロジウム触媒は,C-H機能化のために広く使用されています.
- 既存の触媒はしばしば活性化C−H結合を好み,範囲を制限する.
- 遠隔の非活性化C−H結合の選択的機能化は依然として課題である.
研究 の 目的:
- 選択的なC-H機能化のための新しいキラルディロジウム触媒を開発する.
- 遠隔の非活性化C−H結合を 活性化する 触媒の能力を調べるため
- 複雑な分子合成におけるこの方法の有用性を実証する.
主な方法:
- 新しいキラルディロジウムテトラカルボキシラート触媒Rh2 ((S-2-Cl-5-BrTPCP) の合成.
- C-H機能化反応のためにドナー/受容体カルベンの中間物質を使用する.
- 遠隔の非活性化メチレンC-H結合のサイト選択機能化を使用しています.
主要な成果:
- 触媒Rh2 ((S-2-Cl-5-BrTPCP) 4はC4に近い対称性を示している.
- 遠隔の非活性化されたメチレンC-H結合の高度な場所選択機能化を達成した.
- 反応において高いダイアステレオ選択性とエナチオ選択性を示した.
- 様々なアリルおよびヘテロアリル誘導体に適用できます.
- 自然産物合成の連続C-H機能化に成功している.
結論:
- 開発されたキラルディロジウム触媒は,選択的なC-H機能化のための強力なツールを提供します.
- この方法は,活性化されていないC−H結合をターゲットにすることで,以前の触媒の限界を克服します.
- この方法論は天然製品を含む複雑な分子を合成する大きな可能性を秘めている.
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