触媒的交叉メタテシスによるEとZ三置換アルケンの合成
Thach T Nguyen1, Ming Joo Koh1, Tyler J Mann1
1Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA.
Nature
|January 3, 2018
まとめ
化学者は,アサイクリック三置換アルケンの立体選択合成のための新しい交叉転移法を開発した. このアプローチは以前の制限を克服し,効率的で高度に純粋なEまたはZ同位体生産を可能にします.
科学分野:
- 有機化学
- キャタリシス
- ステレオ選択合成
背景:
- 触媒的交叉メタテシスは極めて重要であるが,ステレオセレクティブのアサイクリック三置換アルケンの合成には方法がない.
- 化学選択性の問題とメチリデン複合体の不安定性が課題です.
研究 の 目的:
- E/Zアサイクル三置換アルケンの効率的でステレオ選択的な合成のための新しいクロスメタテシス戦略を開発する.
- 既存の方法の限界を克服し,複雑なアルケンの同位体へのアクセスを可能にします.
主な方法:
- 前合成されたE-またはZ-三置換アルケンの交叉メタテシス反応を利用した.
- 初期アルケンの材料を簡単に作るためのクロスカップリング反応を用いる.
主要な成果:
- 特殊なステレオ同位体純度 (98%Eまたは95%Zまで) の線形EまたはZ三置換アルケンの効率的な合成を達成した.
- 生物学的活性化合物の簡潔なステレオ選択的合成によって戦略の有用性を実証した.
結論:
- 開発されたクロスメタテシス方法は,有価なアサイクル三置換アルケンの立体選択合成のための堅固な解決策を提供します.
- このアプローチは,インドアゼンBやコイバシンDのような天然製品を含む複雑な分子合成を容易にする.
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