モリブデン (IV) 伸縮型二水素複合体の合成と反応性
Thomas M Cameron1, Carlos G Ortiz, Ion Ghiviriga
1Department of Chemistry and Center for Catalysis, University of Florida, Gainesville, Florida 32611-7200, USA.
Journal of the American Chemical Society
|February 7, 2002
まとめ
モリブデン複合体は水素と反応して二水素複合体を形成する. これらの複合体は,NMRスペクトロスコピーと構造分析によって特徴付けられ,ユニークな結合特性を発揮し,より高い温度でさらに変化します.
科学分野:
- 有機金属化学 有機金属化学
- 協調化化学について
- スペクトル顕微鏡検査です.
背景:
- フォスフィンとアミドリガンドを含むモリブデン複合体は,触媒的な用途に興味があります.
- H2のような小さな分子との低価モリブデンの反応性を理解することは極めて重要です.
研究 の 目的:
- モリブデンの新しい二水素複合体を合成し,特徴づけること.
- 二水素リガンドの結合性質を調査する.
- 二水素複合体の熱安定性と反応性を研究する.
主な方法:
- 核磁共振 (NMR) スペクトロスコーピ (1Hと31P) を用いて特徴を決定する.
- 均衡比率を決定するための変数温度NMR研究.
- T1分析と結合常数測定で二水素結合を検出する.
- 構造的決定のためのX線結晶学.
主要な成果:
- 親モリブデン複合体とH2.2から二水素複合体 [Mo(NPh) ((PMe3) 2 ((H2) ((o- ((Me3SiN) 2C6H4) ] の形成.
- NMRデータは,二水素リガンドの存在と金属中心との相互作用を確認した.
- スペクトロスコピクデータから計算したH-H距離は,H-H結合が有意であることを示しています.
- 二水素複合体は熱分解を経て,アミドリガンドを伴う新しいモリブデン複合体を形成する.
結論:
- 新しいモリブデン二水素複合体が成功裏に合成され,特徴づけられました.
- spetroscopic 証拠は,有意な H-H 結合を持つよく定義された二水素リガンドをサポートします.
- 二水素複合体は熱的不安定性を示し,リガンドの再編成につながります.
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