端末PO複合体のフォスファ-ウィティッグ変換によって形成された異常なPP二重結合
Nicholas A Piro1, Christopher C Cummins
1Department of Chemistry, 77 Massachusetts Avenue, Room 6-435, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|June 10, 2009
まとめ
一酸化化合物複合体とニオビウムフォスフィニデン複合体の間の新しいO-for-PSiR3メタテシス反応により,ユニークなディフォスフェニド複合体が得られます. この複合体は異常な結合を示し,双分子経路で分解される.
科学分野:
- 有機金属化学 有機金属化学
- 無機合成の無機合成とは
- 協調化化学について
背景:
- リン酸を含有するリガンドは,金属器官化学において極めて重要であり,金属中心の反応性と電子特性に影響を与えます.
- メタテシス反応は,ユニークなリガンドフレームワークを持つ新しい金属複合体を合成するための強力な経路を提供します.
- 低座標のリン種の結合と反応性を理解することは,無機化学の進歩に不可欠です.
研究 の 目的:
- 末端のリン酸化物複合体とニオビウム・フォスフィニデン複合体の間のO−対−PSiR3メタテシス反応を調査する.
- その結果生じるディフォスフェニド複合体を特徴付け,その電子構造と結合を解明する.
- 新型ディフォスフェニド複合体の反応性と分解経路を探求する.
主な方法:
- モリブデン・リン酸化物とニオビウム・フォスフィニデン複合体の合成.
- O-for-PSiR3メタテシス反応により,オクソニオビウムおよびディフォスフェニド複合体を形成する.
- ディフォスフェニド複合体の構造的決定のためのX線結晶学.
- 結合の特徴付けをサポートするための密度関数理論 (DFT) 計算.
- ディフォスフェニド複合体とトリフェニルフォスフィンを含む均衡試験.
主要な成果:
- O-for-PSiR3メタテシスは,オクソニオビウム複合体と新しいディフォスフェニド複合体 (iPr3SiPPMo(N[(tBu) ]Ar) 3) を成功裏に生成しました.
- X線結晶学とDFT計算により,d2金属中心に3e-ドナーとして作用するユニークな"単曲線"ディフォスフェニドリガンドが明らかになった.
- ディフォスフェニド複合体は,二分子経路を通って時間とともに分解し,安定した脱出グループとして末端フォスフィド複合体を形成します.
- ディフォスフェニド複合体,PPh3,およびフォスフィニデンの転移産物との間の均衡が確立されました.
結論:
- この研究は,異常な結合モードを持つユニークなディフォスフェニド複合体への新しい合成経路を示しています.
- 特徴づけられたディフォスフェニド複合体は,有機金属化学における低座標のリン酸リガンドの新しいクラスを表しています.
- 観察された分解経路は,これらの新しい複合体のダイナミックな性質と反応性を強調しています.
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