氧墙仍然完好无损:一个四面体扭曲的Co (IV) -Oxo复合体
Jindou Yang1, Hai T Dong2, Mi Sook Seo1
1Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea.
Journal of the American Chemical Society
|October 5, 2021
概括
研究人员描述了一种具有宏环连体的新型 (IV) 氧复合物. 光谱和计算研究发现一个扭曲的,四坐标的中心具有独特的结结构,影响其反应性.
科学领域:
- 无机化学
- 生物有机化学
- 计算化学
背景情况:
- 氧复合物是氧化催化过程中的关键中间体.
- 了解高价值金属氧物种的电子和结构性质是设计高效催化剂的关键.
研究的目的:
- 合成和描述一种新型的 (IV) 氧复合物与N4宏环,12-TBC (1,4,7,10-四-1,4,7,10-四环).
- 通过光谱和理论方法的结合,阐明该复合物的结构,电子和粘合特性.
- 在原子和氧原子转移反应中研究 ((IV) -oxo复合物的反应性.
主要方法:
- 准备和光谱表征 (Co K-边缘XAS,共振拉曼,EPR,MCD) 的 (IV) 氧复合物.
- 密度函数理论 (DFT) 计算以开发结构模型并了解电子属性.
- 支持结构性发现的EXAFS数据分析.
主要成果:
- 通过Co K-edge XAS和共振拉曼光谱证实了 (IV) 氧中间体的形成.
- 根据EPR和EXAFS数据显示存在显著的罗姆比性和结构性扭曲.
- DFT计算揭示了具有CoO··HN键和四坐标中心的联质子结构.
- 通过MCD光谱测试,可以支持所提出的结构,并揭示了Co-oxo π-键的极化.
结论:
- 合成的 (IV) 氧复合体呈现出一种异常扭曲的结构,由分子内键稳定.
- 这种独特的结构图案影响着复合体的电子特性和反应性.
- 该研究提供了有关催化剂的高价值氧物种的基本化学知识.
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