単離可能なコオキソ複合体からのアリファティックC-H結合の酵素のような水酸化
McKenna K Goetz1, Joseph E Schneider1, Alexander S Filatov1
1Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States.
Journal of the American Chemical Society
|December 2, 2021
まとめ
研究者は新しいコバルト-オクソ複合体を開発し,アリファティックC-H結合を効率的に水酸化する. この画期的な発見は 自然の酵素を模倣し 強力な合成酸化メカニズムに 洞察を与えてくれます
科学分野:
- 無機化学
- バイオミメティック・ケミストリー
- キャタリシス
背景:
- アリファティックC−H結合の選択的水酸化は,難しいが貴重な化学変換である.
- 自然はC-H結合を効率的に活性化するために,鉄-オクソ中間物質を使用するサイトクロームP450酵素を使用します.
- 酵素にインスパイアされた合成触媒は,しばしば移行金属-オクソ中間物質を提案するが,多くは強いC-H結合で反応性が欠けている.
研究 の 目的:
- 新しい末端コバルト-オクソ複合体を分離し特徴づけること.
- 暫定的なコバルト-オクソの中間物質のC-H水酸化活性を調べる.
- C-H活性化と水酸化を制御するメカニズム的要因を解明する.
主な方法:
- 新しい端末型Co (III) -オクソ複合体,PhB (AdIm) 3Co (III) Oの合成と特徴付け
- 酸化による一時的なCo ((IV) -オクソ中間物の生成と研究.
- 運動測定 (k1 > 130 s-1 4 °C) と密度関数理論 (DFT) 分析
主要な成果:
- PhB ((AdIm) 3Co ((III) O複合体の分離
- アリファティックC-H水酸化を行うことができる反応性Co ((IV) -オクソ種を生成する.
- エンドルゴニックC-H活性化ステップとエクスペルゴニックラジカルリバウンドステップの実証,全体的な反応を駆動する.
結論:
- 新しいコバルト-オクソシステムは,シトクロームP450酵素に匹敵する急速なC-H水酸化を実現します.
- 反応のメカニズムは,最初のエンダーゴニックC-H活性化と,高度にエクサーゴニックなラジカルリバウンドを含む.
- この明確に定義されたシステムは,生物学的および合成的水酸化プロセスに関する貴重な洞察を提供します.
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