O2がバナジウム (III) トライサニリド複合体と2段階結合し,バナジル以外のバナジウム (V) ペロキソ複合体を形成する
Anthony F Cozzolino1, Daniel Tofan, Christopher C Cummins
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|October 23, 2012
まとめ
この研究は,バナジウム複合体の酸素との反応を調査し,中間種の形成とその後の変換を詳細に説明しています. 研究はまた,これらの反応を制御する方法を模索し,結合したニトリルの酸化につながります.
科学分野:
- 有機金属化学 有機金属化学
- 無機化学 無機化学とは
- 反応の動力学
背景:
- 大量のアミドリガンドを持つバナジウム複合体は,そのユニークな反応性のために興味を惹きます.
- これらの複合体の分子酸素との相互作用を理解することは,触媒と合成アプリケーションにとって極めて重要です.
研究 の 目的:
- 反応経路を解明する V(N[(t) Bu]Ar) ((3) とO(2) の反応経路を解明する
- 酸化過程で形成される中間産物や産物を特徴付ける.
- 反応結果を制御するための戦略を調査し,特に望ましくない経路を抑制する.
主な方法:
- 反応速度をモニタリングし,中間物質を特定するための停止フロー運動学的研究.
- 溶液熱計は,熱力学的パラメータを決定する.
- 反応機構をモデル化するための計算研究.
- 重要な化合物の構造を決定するX線結晶学.
主要な成果:
- 反応は, η(1) -O(2) の中間物質を通過し,その中間物質は, η(2) -O(2) の種に異体化します.
- O(2) が η(2) -O(2) 複合体を形成する結合は,非常にエクソテルミック (-75.0 ± 2.0 kcal/mol) である.
- (t) BuCNの存在下では,反応により望ましい η(2) -O(2) 複合体と酸化ニトリル産物が生じ,分解経路を抑制する.
結論:
- 反応メカニズムは,異なる酸素結合モードを持つ異なる中間物質を含む.
- 計算および実験データは,提案された動力学および熱力学プロフィールを支持しています.
- ニトリルの添加は,反応経路を効果的にリダイレクトし,新しい酸化有機金属化合物の合成を可能にします.
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