フレストラテッド・ペア・ヒドロゲネーションによる安定したボロサイクル・ラジカル
Lauren E Longobardi1,2, Lei Liu1,2, Stefan Grimme1,2
1Department of Chemistry, University of Toronto , 80 St. George Street, Toronto, Ontario M5S 3H6, Canada.
Journal of the American Chemical Society
|February 6, 2016
まとめ
研究者らは,イライラしたルイス・ペア化学を用いて,安定したボロンを含むラジカルを合成した. これらの堅固なラジカルは,H2活性化によって形成され,様々な条件下で安定性を示し,ラジカル化学の新たな可能性を提供します.
科学分野:
- 有機金属化学
- ラジカル・ケミストリー
- メイングループ 化学
背景:
- 安定したメイングループラジカルの合成と分離は化学において重要な課題を提示する.
- フレストラテッド・ルイス・ペア (FLP) の化学は,反応性の種を安定させるための新しいアプローチを提供します.
研究 の 目的:
- 安定したボロン含有ラジカルを合成するために,挫折したルイスペア化学を適用する.
- これらの新しい種の安定性と反応性を調査する.
主な方法:
- H2活性化のために多芳香ダイオンとB ((C6F5) 3) を含む挫折したルイスペア化学を用いた.
- 電子パラマグネティック共振 (EPR) とUV/VIS光譜を用いて合成されたラジカルを特徴づけました.
- 形成メカニズムを探求するために,密度関数理論 (DFT) の計算を使用した.
- 循環式電圧測定とコバルトセンの反応による反応性を調査した.
主要な成果:
- H2活性化によって安定したボロンを含むラジカルの良好な収量を達成した.
- シリカゲルに対する安定性,O2に対する耐性,そしてN2の下の35°Cでの無限の安定性を示した.
- ラジカル形成のメカニズムを支持する実験的および計算的証拠を提供した.
- コバルトセネスを使ってボラートアニオンに 1 電子の化学還元が確認された.
結論:
- うまく合成された 頑丈で分離可能な ボロン含有ラジカル 挫折したルイスペア化学を介して
- 開発された方法は,安定したメイングループラジカルにアクセスするための実行可能な経路を提供します.
- これらの安定したラジカルは 独特の性質と反応性を表しており 合成化学におけるさらなる探求の道を開いています
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