エナチオセレクティブイリジウム触媒アルキル化におけるアルニルカルボネート
David A Petrone1, Mayuko Isomura1, Ivan Franzoni2
1ETH Zürich , Vladimir-Prelog-Weg 3, HCI , 8093 Zürich , Switzerland.
Journal of the American Chemical Society
|March 1, 2018
まとめ
新しい触媒法により,アレニル電子とアルキル亜鉛の反応剤のC ((sp3) -C ((sp3)) 結合が可能になる. このイリジウム触媒反応は,優れた地域制御を持つ,高度にエンアンチオンの濃縮された製品を生み出し,幅広い合成有用性を示しています.
科学分野:
- 有機化学
- キャタリシス
- 合成方法論
背景:
- C ((sp3) -C ((sp3)) 結合形成は有機合成において極めて重要です.
- 複雑な分子合成のためのエナンチオセレクティブの方法の開発は,依然として課題です.
- アレニル電子は,C−C結合形成に特異的な反応性を持っています.
研究 の 目的:
- エナチオコンバージェントのC ((sp3) -C ((sp3) カップリング反応を開発する.
- アレニル電子の結合において高いエナンチオと地域選択性を達成する.
- 合成製品の応用を探求する.
主な方法:
- イリジウム (Ir) 触媒とフォスフォラミド酸オレフィン結合体系を使用した.
- ラセミアルエニル電化剤とアルキル亜鉛反応剤を使用した.
- 実験的および理論的研究を用いて反応機構を調査した.
主要な成果:
- 高濃度のアンチオエニル代替製品 (93-99% ee) を獲得した.
- 完全な地域制御が示され,1,3-ディエネ同位体 (> 50: 1 rr) よりもアレニル製品が優れている.
- ステレオ選択的機能低下反応における製品の有用性を示した.
結論:
- 新しいIr触媒によるC ((sp3) -C ((sp3)) 結合を開発した.
- この方法により,有価なエナチオ濃縮アルエニル化合物が得られます.
- メカニズムは,Ir-調整されたアリルブタディエニリウムπシステムに対する核愛的攻撃を伴う.
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