合理的リガンド設計による銀触媒プロパルギルC-H結合アミネーション
Minsoo Ju1, Emily E Zerull1, Jessica M Roberts1
1Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|July 14, 2020
まとめ
研究者は,非対称なC-Hアミネーションのための新しい銀触媒法を開発し,エナチオ濃縮されたγ-アミノアルコールを生成した. この効率的なプロセスは新しいリガンドを使用し,高い選択性を持つ多用途な製品を提供します.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- 非対称なC-Hアミネーションは,容易に入手可能なC-H結合からキラルアミンを合成するために不可欠である.
- 窒素移転反応は,C-H機能化のための強力な戦略を提供します.
研究 の 目的:
- γ-アルキニル γ-アミノアルコールの地域およびエナチオ選択的合成を開発する.
- 銀触媒によるプロパルギルC-Hアミネーションプロトコルを探るためだ
主な方法:
- 構造-活性関係 (SAR) 分析により開発された新設計のビス・オクサゾリン (BOX) リガンドを使用した.
- サブストラットとして γ-プロパルギルC-H結合を持つアクセシブルカルバマートエステルを使用しています.
- 密度関数理論 (DFT) の計算を用いて反応機構を調査した.
主要な成果:
- γ-アルキニル γ-アミノアルコールの高度な地域およびエナチオ選択的合成を達成した.
- 良質の多用途製品と優れたエナチオ選択性 (90-99% ee) を獲得した.
- 推定のAg-ニトロンの中間体によるエナチオ決定性水素原子移転 (HAT) を含むメカニズムを提案した.
結論:
- 開発された銀触媒プロパルギルC-Hアミネーションは,キラルγ-アミノアルコールを製造するための効果的な方法である.
- 新しいBOXリガンドは,高いエナチオ選択性を達成するための鍵です.
- DFT計算は,HATステップにおけるエナンチオセレクティビティの起源についての洞察を提供します.
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