跨-W ((Cmesityl) ((dmpe) 2H:揭示了极极的W-H键和液态和固态中的H流动性
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
概括
新的复合物被合成并研究为动态交换过程. 在一个复合体中,W-D键被发现为85%的离子,在溶液和固态中观察到动态交换.
科学领域:
- 有机金属化学 有机金属化学
- 固态化学 固态化学
- 反应动力学 反应动力学
背景情况:
- 带有庞大的配体的复合物对催化和材料科学有兴趣.
- 了解有机金属化合物的动态过程对于预测反应性至关重要.
- 同位素标记为阐明反应机制提供了一个强大的工具.
研究的目的:
- 为了合成和表征新的同位素复合物.
- 研究溶液和固态中的动态交换过程.
- 为了确定-键的离子性.
主要方法:
- 同位素复合物的合成.
- 核磁共振 (NMR) 光谱与标签.
- 进行X射线衍射研究.
- 准弹性中子散射 (QENS).
主要成果:
- 复合物跨-W (Cmesityl) (C (H,D) 3) 2PCH2CH2P (C (H,D) 3) 2) 2 (H,D) 1-4已经准备好了.
- 复合体2中的WD键表现出85%的离子性,其四极合常量 (DQCC) 为34.1kHz.
- 综合体1展示了动态交换过程,包括HW/HW,HW/ortho-Mesityl和溶液中的HW/H2以及固体中的HW/Mep.
- 在60°C时,观察到复合物1到carbyne复合物5的同质化.
- 在固态状态下,QENS为HW/Mep交换提供了5kcal/mol的激活障碍.
结论:
- 动态交换过程显著影响这些复合物的溶液和固体状态的行为.
- W-D 键具有很高的离子性质.
- 通过综合光谱和散射技术获得了对异构化和交换通路的详细机械洞察.
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