同质三价三 (基) 稀土化合物
Aradhana Pindwal1,2, KaKing Yan1,2, Smita Patnaik1,2
1U.S. DOE Ames Laboratory, Iowa State University , Ames, Iowa 50011, United States.
Journal of the American Chemical Society
|October 10, 2017
概括
新的稀土基复合物表现出强大的Ln-Si键和动态交换过程. 这些发现为有机金属化学中的新型合成应用提供了潜力.
科学领域:
- 有机金属化学
- 稀土化学
- 无机化学
背景情况:
- 兰类有机金属化合物由于其独特的电子特性和潜在的催化应用而引起人们的兴趣.
- 开发稳定,明确的基复合物对于探索它们的反应性至关重要.
- 了解这些复合物的结合和动态行为是它们合成实用性的关键.
研究的目的:
- 合成和表征新型同质三基稀土复合物.
- 研究结构特征,特别是二次Ln-Si相互作用.
- 阐明这些复合物的动态交换过程和同位素效应.
主要方法:
- 从类三化物和KC的同质三基复合物 (Ln{C{SiHMe2) 3}3) 的合成.
- 测定固态结构和伪C3对称性的X射线衍射研究.
- 可变温度核磁共振 (NMR) 光谱用于研究动态交换过程和同位素效应.
- 密度函数理论 (DFT) 计算以建模中间体和反应途径.
主要成果:
- 在高产量中合成了同结构同质三基稀土复合物 (Ln = La,Ce,Pr,Nd).
- X射线衍射揭示了具有显著的二次Ln-Si相互作用的伪C3对称结构.
- 在室温下,NMR研究表明Ln-Si和Si-H部分的快速交换,在低温下具有分辨率.
- 可变温度的NMR和DFT计算提供了对交换机制的洞察力,并揭示了反向的动态同位素效应.
结论:
- 合成的稀土基复合物在结构上强大,在溶液中表现出动态行为.
- Ln-Si结合和交换机制的特征很好,提供了基本的见解.
- 这些稳定的复合物有望在合成有机金属化学中的多种应用,包括合成新的类化合物.
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