trans-W ((Cmesityl) ((dmpe) 2H: 液体および固体状態で極極性のあるW-H結合とH移動性を明らかにした
Fenglou Zou1, Franck Furno, Thomas Fox
1Anorganisch-chemisches Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
Journal of the American Chemical Society
|May 15, 2007
まとめ
新しいボルンガム複合物は合成され,ダイナミックな交換プロセスのために研究されました. ある複合体のW-D結合は85%イオン性であることが判明し,溶液と固体状態で動的交換が観察されました.
科学分野:
- 有機金属化学 有機金属化学
- 固体化学 固体化学
- 反応ダイナミクス 反応ダイナミクス
背景:
- 大容量のリガンドを持つボルフステンの複合体は,触媒と材料科学に興味があります.
- 有機金属化合物のダイナミックなプロセスを理解することは,反応性を予測するために重要である.
- 同位体ラベリングは,反応機構の解明のための強力なツールを提供します.
研究 の 目的:
- 新しい同位体型ボルンガム複合体を合成し,特徴づけること.
- 溶液と固体状態におけるダイナミックな交換プロセスを調査する.
- トングステン-デウテリウム結合のイオン性を決定する.
主な方法:
- イソトポメア型ボルンガム複合体の合成.
- デウテリウムラベル付きの核磁気共振 (NMR) スペクトロスコーピー.
- X線 difrraction研究.X線 difrraction研究.X線 difrraction研究.X線 difrraction研究.X線 difrraction研究.X線 difrraction研究.
- 準弾性中性子散射 (QENS) とは
主要な成果:
- 複合体トランス-W ((Cmesityl) ((C ((H,D) 3) 2PCH2CH2P ((C ((H,D) 3) 2) 2) 2 ((H,D) 1-4が準備されました.
- 複合体2のWD結合は85%のイオン性を示し,デュテリウム四極結合定数 (DQCC) は34.1kHzである.
- コンプレックス1は,HW/HW,HW/オルトメシチル,溶液中のHW/H2および固体状態のHW/Mepを含むダイナミック交換プロセスを表示しました.
- 複合体1からカルビネ複合体5へのイソメリゼーションは60°Cで観察された.
- QENSは,固体状態のHW/Mep交換に5kcal/molの活性化バリアを提供した.
結論:
- ダイナミックな交換プロセスは,溶液と固体状態のこれらのボルンガム複合体の振る舞いに大きく影響します.
- W-D結合は,高いレベルのイオン特性を持っています.
- アイソメリゼーションと交換経路に関する詳細なメカニズム的な洞察は,光譜と分散技術の組み合わせによって得られた.
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