高化物计数的八面体,[Rh6(PR3) 6H12][BArF4]2:在温和条件下合成,结构和可逆的吸收
Simon K Brayshaw1, Michael J Ingleson, Jennifer C Green
1Department of Chemistry, University of Bath, UK.
Journal of the American Chemical Society
|May 4, 2006
概括
研究人员描述了一个新的类型的集群,[Rh () 6 () PR () 3 () 6 () 12 () ][BAr () F () 4 () 2],其表现出独特的结构和可逆的H () 2吸收. 这些过渡金属集群为结合和反应性提供了新的见解.
科学领域:
- 无机化学 无机化学
- 有机金属化学 有机金属化学
- 材料科学 材料科学 材料科学
背景情况:
- 晚期过渡金属集群通常具有pi-接受器连接体.
- 早期的过渡金属集群经常显示边缘桥接pi-donor连接体.
研究的目的:
- 合成和描述一种新型的六合集群类.
- 研究这些集群的结构和电子特性.
- 探索它们的反应性,特别是2的吸收和释放.
主要方法:
- 单晶X射线晶体学用于固态结构的确定.
- 脉冲梯度旋回回声NMR光谱法,以评估溶液的行为.
- 电子喷雾电离质谱仪 (ESI-MS) 用于配方确认.
- 密度函数理论 (DFT) 计算用于电子结构分析.
主要成果:
- 实现了[Rh(6) ((PR(3)) ((6) H(12) ]][BAr(F) ((4) ] ((2) (1a, 2a) 的合成,其中具有具有边缘桥接合物联体的独特结构.
- 发现集群在溶液中是稳定的,并且能够进行可逆的H2吸收,形成Rh6PR3H16BArF42) (1b,2b).
- DFT的计算支持了结构性赋值,并揭示了涉及20个轨道的结合框架.
结论:
- 发现了一种具有早期过渡金属结构的新类六集群.
- 这些集群表现出可逆的H(2) 结合,这表明在催化中具有潜在的应用.
- 该研究提供了对新型过渡金属集群的结构,结合和反应性的基本见解.
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