非方向ボリレーションによる強いアルキルC−H結合の多様な機能化
Raphael Oeschger1, Bo Su1, Isaac Yu1
1Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|May 16, 2020
まとめ
この研究は,選択的な炭素-水素結合のボリル化のための新しいイリジウム触媒を導入する. 主要および二次C−H結合の効率的な機能化を可能にし,合成化学の可能性を拡大します.
科学分野:
- 合成有機化学
- カタリシス
- 有機金属化学
背景:
- 炭素-水素 (C-H) 結合の選択的機能化は,合成化学における重要な課題である.
- 副次C-H結合を回避する主C-H結合の非誘導的機能化は特にまれである.
- 以前のC-Hボリレーション方法は,しばしば遅い反応速度と大きな基板過剰を必要とした.
研究 の 目的:
- C−H結合の選択的ボリル化のための高活性な触媒を開発する.
- 主要なC−H結合の無方向ボリル化を達成するために,制限反応剤として基板を使用します.
- 主要なサイトが利用できない場合,強い二次C-H結合のボリレーションを可能にします.
主な方法:
- 2-メチルフェナントロリンと連携したイリジウム触媒の開発.
- 様々な有機基質のボリル化における触媒の活性に関する調査.
- 生成された炭素-ボロン結合を含む後の反応の探索.
主要な成果:
- イリジウム触媒は高い活性を示し,基板限定C-Hボリレーションを可能にしました.
- 主要なC−H結合の選択的機能化は,競合する二次C−H結合反応なしに達成された.
- 主要部位が遮断されたとき,触媒は強い二次C−H結合のボリル化も促進した.
- その後,炭素-ボロン結合の変換により,さまざまなC-CとC-ヘテロ原子結合装置ができました.
結論:
- 新しいイリジウム触媒は,主および二次部位を含む,効率的かつ選択的なC-Hボリレーションを容易にする.
- この方法は,以前のアプローチの限界を克服し,制限反応剤として基板で機能化することを可能にします.
- 開発されたボリレーション戦略は,有機分子にこれまでアクセス不可能な位置に様々な結合を設置するための新しい道を開きます.
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