四次炭素ステレオセンターにおける核性置換
Veeranjaneyulu Lanke1, Ilan Marek1
1Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City 3200009, Haifa, Israel.
Journal of the American Chemical Society
|March 7, 2020
まとめ
サイクロプロピルカルビノール誘導体は,核愛置換によって効率的にアサイクリック化合物に変換されます. このプロセスは,高い地域性およびステレオ選択性を持つ単一のダイアステロエーマーを生成し,新しい合成経路を提供します.
科学分野:
- 有機化学
- ステレオ選択合成
- 反応メカニズム
背景:
- サイクロプロピルカルビノール誘導体は,有価な合成中間物質である.
- 核愛置換反応における地域性およびステレオ選択性の制御は,持続的な課題である.
研究 の 目的:
- サイクロプロピルカルビノール誘導体の地域性およびステレオ選択的核性置換を調査する.
- エナティオメリックに濃縮されたアサイクリック化合物を製造するための効率的な方法を開発する.
主な方法:
- サイクロプロピルカルビノール誘導体を原料として利用する.
- クォーターナリー炭素中心を標的とした核愛置換反応を用いる.
- 商業的に利用可能なアルキンの触媒反応段階.
主要な成果:
- 四次性炭素で地域性およびステレオ選択性核性置換を達成した.
- 構成の純粋な逆転が示され,単一のダイアステロエーマーが得られる.
- ダイアステロエーマー的に純粋でエナチオマー的に濃縮された三次アルキルハリドとエステルを成功して合成した.
結論:
- 観察された選択性は,提案されたサイクロブトニウム中間物質に起因する.
- この方法は,数少ないステップで価値あるアサイクル製品への容易なアクセスを提供します.
- 単純な前体から多様な機能化されたアサイクリック化合物を製造することができる.
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