ニッケル (II) アシルペロキソ複合体の構造的特徴と酸化反応性
Jun Nakazawa1, Shota Terada, Masaki Yamada
1Department of Material and Life Chemistry, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan. jnaka@kanagawa-u.ac.jp
Journal of the American Chemical Society
|April 16, 2013
まとめ
この研究は,硫化物とオレフィンの電気的酸化,および炭化水素からH原子抽出のための能力を実証する新しいニッケル (II) - アシルペロキソ複合体, [Ni (Tp) (CF3Me) (κ) (2) - mCPBA) ] を詳細に説明しています.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- 無機化学 無機化学とは
背景:
- ニッケル複合体は,有機合成における汎用的な触媒である.
- アシルペロキソリンガンドは酸化反応を媒介することができる.
- 反応メカニズムを理解することは,触媒設計において極めて重要です.
研究 の 目的:
- 新しいニッケル ((II) - アシルペロキソ複合体を合成し,特徴づけること.
- 複合体の酸素化とH原子抽象化能力を調査する.
- 反応の動力学とメカニズムを解明する.
主な方法:
- ニッケル ((II) - アシルペロキソ複合体の分離と完全な特徴付け.
- 硫化物やオレフィンによる電友性酸化反応.
- 炭化水素による水素原子抽象反応.
- 運動学研究 (ミカエリス・メンテン,二次運動学).
主要な成果:
- ニッケル (((II) - アシルペロキソ複合体 [Ni (((Tp (((CF3Me)) (((κ (((2) -mCPBA)) ]が成功して合成され,特徴づけられました.
- 複合体は硫化物とオレフィンの電気的酸化を示し,チオアニゾールに対するマイケリス・メンテンの運動学を示している.
- また,第二次動力学に従って,活性化されたC-H結合のためのH原子抽象能力も示しています.
- 証拠は,より反応性の低い炭化水素のためのO-O分割された中間物質を含む代替経路を示唆しています.
結論:
- 新型ニッケル ((II) - アシルペロキソ複合体は,様々な有機基板に対する効果的な酸化剤です.
- 反応のメカニズムは,基板の反応性によって異なるが,不変の複合体とO-O-割れた中間体の両方を含む.
- この研究は,ニッケル触媒による酸化反応の範囲を拡大する.
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