ディオキシゲネーゼ経路による分子酸素の活性化は,近隣のセレニウム部位を持つルテニウムビス-ビピリジン化合物によるものです
Alexander Laskavy1, Linda J W Shimon, Leonid Konstantinovski
1Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, Israel 76100.
Journal of the American Chemical Society
|December 18, 2009
まとめ
ルテニウムビピリジン複合体は,O−O結合の割れ方によって分子酸素 (O(2) を活性化させます. その結果生成される中間物質[Ru](O) ((2) は,触媒性酸化において強力な酸素伝達剤として作用する.
科学分野:
- 無機化学 無機化学とは
- 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
背景:
- ルテニウム (II) ビピリジン複合体は,汎用的な触媒である.
- 分子酸素 (O(2) の活性化が酸化反応に不可欠である.
- O2の活性化メカニズムを理解することは,効率的な触媒の開発の鍵です.
研究 の 目的:
- ルテニウム (((II) ビピリジン複合体とO (((2) の分子内反応を調査する.
- O-O結合の割れた産物とその反応性を特徴づける.
- O(2) アクティベーションと酸素伝達のメカニズムを解明する.
主な方法:
- ルテニウム (II) 複合体とフェニルセレニウムテザーの合成と分離.
- 1,1,1,3,3,3-ヘクサフッロロ-2-プロパノール (HFIP) でO(2) と反応する.
- X線 difraktion,ESI-MS,およびNMRスペクトロスコピーによる構造的特徴付け.
- 磁気感受性の測定とDFT計算.
- トリフェニルフォスフィンとアルケンの酸素伝達に関する研究.
主要な成果:
- 安定したO−O結合が形成され,ルテニウム・オクソ・セレニウム種が分裂した[Ru](O) ((2).
- X線 difraktionにより,2つのRu-O-Se部分を持つ構造が確認されました.
- [Ru](O)(2) は,溶液中のパラマグネティックであると特定され,トリプルまたはビラジカル基底状態を示唆しました.
- DFTの計算はシングレット基底状態と酸化セレニウムを予測した.
- [Ru] (((O) ((2) は,2つの酸素原子をトリフェニルフォスフィンや2,3-ジメチル-2-ブーテンなどの基板に効率的に転送しました.
- 触媒酸化試験では,O2のダイオキシゲネーゼ型活性化が示された.
結論:
- ルテニウム複合体は,O−O結合の割れ方による分子内O2活性化を経験する.
- [Ru](O)(2) は,両方の酸素原子を転送できる重要な中間物質です.
- この研究は,ルテニウム複合体によるO(2) 活性化に関する構造的および機械的洞察を提供します.
- この発見は,新しい触媒酸化プロセスの開発に寄与する.
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