陽子結合電子移転による触媒性オレフィン水酸化
David C Miller1, Gilbert J Choi1, Hudson S Orbe1
1Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|October 7, 2015
まとめ
研究者はイリジウム光触媒を用いた分子内水酸化のための新しい触媒システムを開発した. この方法は,アルケンの機能化のための協調型陽子結合電子移転 (PCET) を介して,アミドからアミド基を効率的に生成します.
科学分野:
- 有機化学
- 光触媒
- カタリシス
背景:
- 分子内ヒドロアミデーションは貴重な合成変換である.
- 活性化されていないオレフィンと単純なアミド誘導体の活性化はまだ困難です.
- これらの反応のための効率的な触媒システムの開発は極めて重要です.
研究 の 目的:
- 活性化されていないオレフィンの分子内ヒドロアミデーションのための新しい三元触媒システムを報告する.
- シンプルなN-アリルアミド誘導体を基質として利用する.
- アミド活性化とラジカル生成のメカニズムを解明する.
主な方法:
- イリジウム複合体を光触媒として使用する.
- PCET (協調型陽子結合電子移転) を媒介するために弱いリン酸塩を用いる.
- チオフェノールコカタリストを組み込み,ラジカル移転とカタリスト再生を容易にする.
主要な成果:
- このシステムは,活性化されていないオレフィンの分子内ヒドロアミデーションを成功させる.
- PCET経由でアミド活性化が行われ,反応性アミド基が生成される.
- PCETによる選択的アミド同解は,チオフェノールがある場合でもメカニズム研究によって確認されている.
結論:
- 開発された三元触媒システムは効率的な分子内ヒドロアミデーションを可能にします.
- PCETはアミドを活性化し,アミド基を生成する重要なメカニズムです.
- このシステムは,チオフェノールコカタリストの存在で選択性と強度を示しています.
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