在的钉复合体中,二的温度和溶剂依赖的结合
Inigo Göttker-Schnetmann1, D Michael Heinekey, Maurice Brookhart
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3290, USA.
Journal of the American Chemical Society
|December 21, 2006
概括
标记的复合物表现出温度和溶剂依赖的行为. 同位素转移和合常数表明有一个延长的二联体,由平衡化物和二结构的模型解释.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学
- 频谱学是一种光谱学.
背景情况:
- 复合物与化物连接体在催化过程中至关重要.
- 了解连接体动态和结合是反应机制的关键.
- 标签提供了对联体行为的洞察.
研究的目的:
- 为了合成和表征用标记的复合物.
- 为了研究温度和溶剂对联结体结构的影响.
- 为了阐明H2合体和化物环境的性质.
主要方法:
- 用标记 (p-XPOCOP) 的IrH2-xD_x复合物的合成.
- 使用1H和2DNMR进行光谱分析.
- 可变温度和溶剂研究.
- 核自旋格子放松度的测量 (T1 ((min)).
主要成果:
- 观察到显著的温度和取决于溶剂的同位素转移以及高清合常量 (JHD).
- 在非极性溶剂 (烯,烯) 中发现了延长型H2配体的证据.
- 复合物6-d1在化溶剂中显示JHD=0Hz,具有很大的温度依赖的同位素效应.
- 这些影响归因于水化物环境的非统计占用.
结论:
- 实验数据支持一个两组件模型.
- 建议在化Ir (III) 二化物和Ir (I) 二物种之间进行快速平衡.
- 这种动态平衡解释了观察到的温度和依赖溶剂的现象.
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