端末フォスフィニデンの機能性を有する中性およびズウィテリオン低座標チタン複合体. Ti-P多重結合に関する構造的,光譜的,理論的,および触媒的研究
Guangyu Zhao1, Falguni Basuli, Uriah J Kilgore
1Department of Chemistry and Molecular Structure Center, Indiana University, Bloomington, IN 47405, USA.
Journal of the American Chemical Society
|October 13, 2006
まとめ
末端のフォスフィニデンのリガンドを持つ新しいチタン ((IV) 複合体は,アルファ-水素抽出と移行反応を使用して合成されました. これらの複合体は,最も短いTi=P結合を示し,重要な有機変換を触媒化する.
科学分野:
- 有機金属化学 有機金属化学
- メイングループ 化学
- カタリシス カタリシス カタリシス
背景:
- 末端フォスフィニデンの複合体は,分離および研究が難しい反応性中間物質です.
- タイタンの複合体は,異常なリガンドを安定させるためのユニークな電子およびステリック特性を提供します.
- フォスフィニデン複合体の合成と反応性を理解することは,新しい触媒方法の開発に不可欠です.
研究 の 目的:
- 末端のフォスフィニデンのリガンドを含む新しいチタン (IV) 複合体を合成し,特徴づけること.
- これらのフォスフィニデンの複合体の反応性を,サイクル添加および触媒反応で調査する.
- Ti=P結合の電子的および構造的性質,およびその反応性への影響について調べる.
主な方法:
- タイタンの前駆体からアルファ水素抽出および移住反応によるチタン (IV) フォスフィニデンの複合体の合成.
- 溶液および固体状態での多核性NMRスペクトロスコーピー (31P NMR) を使用した特徴付け.
- 結合と電子構造を明らかにするための計算研究 (DFT).
- ハイドロフォスフィネーションおよびカルボアミネーション反応における触媒活性の評価.
主要な成果:
- 最初のフォスフィニデンズウィテリオン複合体を含む3つのチタン (IV) フォスフィニデン複合体の合成に成功しました.
- これらの複合体は,最も短いTi=P結合と線形フォスフィニデンの幾何学を示しています.
- 溶液および固体状態の31PのNMRデータは,フォスフィニデネ・リン酸化物の化学的シフトが著しくシールドされていることを示しています.
- DFTの研究では,端末のフォスフィニデンが,偽のTi[トリプル結合]P結合によって安定することを示唆しています.
- ズウィテリオン複合体は,ディフェニラセチレンの水リン酸化を触媒化し,カルボアミネーション前触媒として作用する.
結論:
- 新型チタニウム (IV) フォスフィニデンの複合体は,アルファ水素抽出と移行経路を通じてアクセスできます.
- 合成された複合体は,例外的に短いTi=P結合を含むユニークな構造および電子特性を有しています.
- これらのフォスフィニデンの複合体は,有機合成における触媒としての大きな可能性を示しています.
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