インドルリングの非対称C2-C3サイクロペンタヌレーション
José Barluenga1, Eva Tudela, Alfredo Ballesteros
1Instituto Universitario de Química Organometálica Enrique Moles, Unidad Asociada al C.S.I.C., Universidad de Oviedo, Julián Clavería 8, 33006 Oviedo, Spain.
Journal of the American Chemical Society
|January 30, 2009
まとめ
チラルのボルンガム (((0) カーベンの複合体は [3+2] サイクル反応を促進する. このプロセスは,エナティオメリックに純粋なインドルとテトラヒドロピリジンが融合したサイクロペンテノンを効率的に合成します.
科学分野:
- 有機金属化学 有機金属化学
- オーガニック・シンセシス オーガニック・シンセシス
- アシンメトリック・カタリシス
背景:
- キラルカルベン複合体は,価値ある合成中間物質である.
- エナチオセレクティブサイクリング反応の開発は,複雑な分子合成に不可欠です.
研究 の 目的:
- トングステンのキラル型非ラセミックアルキニル (((アルコキシ)) カーベンの複合体 (((0) の [3+2) サイクリングを調査する.
- エナティオメリックに濃縮された溶融サイクロペンテノンの骨格を合成するために.
主な方法:
- 使用されたキラル非ラセミックアルキニル (alkynyl) (((アルコキシ) カルベンのコンプレックスである (tungsten) (((0)).
- [3+2]サイクル化反応を行った.
- チラルクロマトグラフィを用いてエナティオメリック純度について分析した製品.
主要な成果:
- アルファメチルインドールと1,6-ジメチル-1,2,3,4-テトラヒドロピリジン誘導体を成功して合成した.
- 2,3-インドリン融合サイクロペンテノンと2,3-ピペリジン融合サイクロペンテノン骨格の形成が達成されました.
- 96-99%e.e.の範囲で非常に高いエナティオメール純度を持つ製品を取得しました.
結論:
- チラルのボルンガム (((0) カーベンの複合体は,エナチオセレクティブ [3+2] サイクライゼーションの効果的な触媒である.
- この方法論は,エナティオメリックに純粋な溶融サイクロペンテノンシステムへの直接的な経路を提供します.
- 高いエナティオメリック過剰は,非対称合成におけるこのアプローチの有用性を示しています.
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