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一个正方形平面的Th (III) 复合体的分离:Th (OC) 的合成和结构
Daniel N Huh1, Saswata Roy1, Joseph W Ziller1
1Department of Chemistry , University of California , Irvine , California 92697 , United States.
Journal of the American Chemical Society
|July 24, 2019
概括
合成并描述了具有正方形平面几何的新 (III) 复合物. 这些发现代表了f元素复合体这种协调的第一个例子,揭示了独特的结构和电子特性.
科学领域:
- 有机金属化学
- 无机化学
- 协调化学
背景情况:
- 复合物通常具有高协调数的特征.
- 探索像这样的f元素的低氧化状态对于理解它们的反应性至关重要.
- 合成具有不寻常几何形状的稳定f元素复合体仍然是一个重大挑战.
研究的目的:
- 合成和结晶学描述新的 (III) 复合物.
- 研究降低 (IV) 前体的结构影响.
- 探索由此产生的 (III) 物种的电子特性和协调几何.
主要方法:
- 在THF中使用KC8或Li来降低ThO6H2tBu2-2,6Me-4) 4.
- 合成盐的单晶X射线衍射分析.
- 电子磁共振 (EPR) 光谱.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 两个新的 (III) 复合物的分离和表征:[K (THF) 5 (Et2O) ][Th (OC6H2tBu2-2,6Me-4) ]和[Li (THF) ][Th (OC6H2tBu2-2,6Me-4) ].
- 发现离子的前所未有的正方形平面坐标几何,金属和四个氧原子共平面.
- EPR光谱证实一种基于金属的激素, 符合DFT计算预测低SOMO的6d特征.
结论:
- 减少 (IV) 化物复合物可以产生稳定的 (III) 物种.
- 大量的 tert-butyl 替代剂在强制执行不同寻常的正方形平面几何学上发挥着至关重要的作用.
- 这项研究扩展了已知的f元素的协调化学,并提供了对其电子结构的洞察.
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