カーボカチオンに対する調整誘発型ステレオ制御:ラセミック三次アルコールの非対称的還元性脱酸素化
Mayuko Isomura1, David A Petrone1, Erick M Carreira1
1ETH Zürich , Vladimir-Prelog-Weg 3 , HCI, 8093 Zürich , Switzerland.
Journal of the American Chemical Society
|February 21, 2019
まとめ
研究者は,三次カルボケーションのステレオ選択反応を可能にする,非対称な触媒の新しいドッキング戦略を開発した. この方法は,高選択性を持つ第3次アルコールの最初のエナチオ選択的還元性脱酸素化を実現します.
科学分野:
- 有機化学
- カタリシス
- 非対称合成
背景:
- 三次カルボケーションは,触媒でステレオ選択的に制御することが困難である.
- この制限は,非対称合成における中間物質としての使用を制限している.
研究 の 目的:
- 三次カルボケーションに対するステレオ選択的核愛攻撃の方法を開発する.
- 三次アルコールの最初のエナチオセレクティブ・リダクティブ・デオキシゲン化を実現する.
主な方法:
- キラル型変異金属触媒への可逆基板調整を用いたドッキング戦略.
- ハンツシュエステルの新型アナログをヒドリド源として使用した.
- 詳細なメカニズム研究を行いました
主要な成果:
- 三次カルボケーションに対する高度にステレオセレクティブな核愛性の攻撃を達成した.
- エナチオメア過剰 (ee) が最大96%に達する第3次アルコールのエナチオセレクティブ還元性脱酸素化が実証された.
- 高い地域選択性 (最大50:1rr) が得られた.
結論:
- ドッキング戦略は,カルボケーション中間物質の精密なステレオ化学制御を可能にします.
- この突破は,三次カルボケーションを含む非対称な触媒の新たな道を開く.
- 開発された方法は,三次アルコールのエナチオ選択的脱酸素化のための堅固な経路を提供します.
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