ピリジンのC-α-モノボリレーションによる化学分岐性オルガノランタニド触媒
Jacob O Rothbaum1, Alessandro Motta2, Yosi Kratish1
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, United States.
Journal of the American Chemical Society
|September 8, 2022
まとめ
オルゴランタニド触媒は,ピリジンの選択的アルファ・モノボリレーションを可能にします. この化学分岐アプローチは 価値ある有機分子と 機能的な材料を合成するための 新しい経路を提供します
科学分野:
- 有機金属化学
- カタリシス
- 合成有機化学
背景:
- ピリディノイドアジンのC-H活性化と機能化は,天然製品,医薬品,および材料の合成に不可欠である.
- アジンのアルファ位置の機能化は,触媒の調整とピリジンの電子欠乏を含むステリックおよび電子的要因のために困難である.
研究 の 目的:
- アジンの選択的アルファ単一機能化のための地球豊富な触媒を開発する.
- 有機製品に構造的多様性を導入するための合成化学的方法論を実現する.
主な方法:
- 18種類のピリジンのアルファ・モノボリレーションのために,Cp*2LuCH(TMS) 2を用いたオルゴランタニド触媒を用いた.
- 反応経路を明らかにするために,実験的および理論的メカニズム研究を使用した.
- ランタニド同一性と基質の電子特性による触媒選択性の影響を調査した.
主要な成果:
- オルゴランタニド触媒を用いた多様なピリジンの選択的アルファ・モノボリレーションを達成した.
- ランタニドイオンと基質の電子特性によって前例のない触媒化学分岐を証明した.
- C-Hで活性化されたeta(2) -ランタニド-アジン複合体の中間物質を特定し,シグマ結合転移を含むメカニズムを提案した.
結論:
- ピリジンの選択的アルファ・モノボリレーションのための新しいオルガノランタニド触媒法を開発した.
- 選択的なC-H機能化またはB-N結合形成の脱オロマ化を可能にするランタニド系触媒化学分岐を展示した.
- 有機合成におけるさらなる機能化のための貴重な前駆物質を提供した.
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