イリジウム触媒による非対称ボリレーションの非活性化メチレンC−H結合
Ronald L Reyes1,2, Tomohiro Iwai1, Satoshi Maeda1,2
1Department of Chemistry, Faculty of Science , Hokkaido University , Sapporo 060-0810 , Japan.
Journal of the American Chemical Society
|April 16, 2019
まとめ
この研究は,新しいイリジウム触媒を用いて,ピリジンとアゾールにおけるC ((sp3) -H結合の高度なエナンチオセレクティブのボリル化を示している. この方法は,キラル反応ポケットを介してエナチオトープメチレン群を正確に分化します.
科学分野:
- 有機化学
- カタリシス
- 非対称合成
背景:
- C-H結合の機能化は合成化学の重要な分野である.
- 価値ある有機分子のエナチオセレクティブ合成は依然として重要な課題です.
研究 の 目的:
- 活性化されていないメチレンC ((sp3) -H結合のボリル化のための高度なエナンチオセレクティブの方法を開発する.
- 計算的方法を用いたエナチオ選択的微分化のメカニズムを調査する.
主な方法:
- イリジウムBINOL基のキラルモノフォスフィート触媒を用いた.
- 人工力誘導反応 (AFIR) 方法による量子化学計算を適用した.
主要な成果:
- 2-アルキルピリジンと2-アルキル-1,3-アゾール誘導体の高度なエナンチオセレクティブのボリレーションを達成した.
- 計算による研究では,モノフォスフィート-Ir-tris (ボリル) 複合体によって形成された狭いキラル反応ポケットが明らかになった.
- 異質C−H結合の差異化に関与する複数の非共性相互作用を特定した.
結論:
- 開発された触媒システムは,挑戦的なC−H結合の効率的でエナチオ選択的なボリレーションを可能にします.
- この研究は,限られたキラル環境における非共性相互作用による非対称的誘導に関する機械的洞察を提供します.
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