加强对氧化 (IV) 复合物的结构功能关系的理解
Priya Singh1, Yuri Lee1, Jaycee R Mayfield1
1The University of Kansas, Department of Chemistry and Center for Environmentally Beneficial Catalysis, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States.
Inorganic chemistry
|June 14, 2023
概括
这项研究合成了具有不同连接体场的-氧合物复合物,以探索它们的反应性. 连接体场强度和固体因素显著影响碳化合物和离子的氧化率.
科学领域:
- 无机化学 无机化学
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
背景情况:
- 氧复合物在各种氧化反应中至关重要.
- 了解连接体环境对反应性的影响,是催化剂设计的关键.
研究的目的:
- 合成和表征 (II) 和氧 (IV) 复合物,具有不同的赤道连接体场强度.
- 调查联结体场强度和固体体积的变化如何影响这些复合物的氧化反应.
主要方法:
- 复合物的合成和结构特征.
- 光谱分析,包括电子吸收光谱.
- 使用碳化合物和 thioanisole 氧化反应性的研究.
- 使用密度函数理论 (DFT) 计算结合解离自由能量 (BDFEs) 的计算分析.
主要成果:
- 成功合成和表征了具有不同赤道连接体场强度的复合体.
- [MnIV(O) ((N4pyMe2) ]2+表现出最弱的赤道配体场,而[MnIV(O) ((N2py2I) ]2+显示出最强的.
- [MnIV(O)(N3pyQ) ]2+复合体在C-H键和离子氧化中表现出高反应性.
- 发现,不仅仅是连接体场强度,还包括体因素,都会抑制[MnIV(O) ((N4pyMe2) ]2+复合体的反应性.
- 通过DFT计算的BDFEs与离子氧化率 (MnIVO BDFEs) 相关性很好,并且与碳化合物氧化率 (MnIIIO-H BDFEs) 显示分散.
结论:
- 连接体场强度和硬质体量是-氧合物复合物的反应性的关键决定因素.
- 计算BDFEs与实验氧化率之间的相关性为反应机制提供了洞察力.
- 这项工作有助于合理设计高效的基于的氧化催化剂.
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