电荷和溶剂对瓦纳迪尔盐-皇冠复合物的氧化反应的影响
Hien M Nguyen1, Harry W T Morgan2, Teera Chantarojsiri3
1Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States.
The journal of physical chemistry. A
|June 14, 2023
概括
瓦纳中心附近的带电群影响氧化还原行为. 皇冠以太复合物与各种金属离子显示基于离子电荷和溶剂极性改变的还原潜力,突出溶剂和离子效应.
科学领域:
- 协调化学 协调化学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 在氧化还原活性金属中心附近的带电组调节电场,影响氧化还原潜力和催化活性.
- 瓦纳基盐复合体是研究金属中心反应性的已建立平台.
研究的目的:
- 为了合成和电化学研究,使用含有各种金属酸的皇冠乙烯功能化的瓦纳基酸复合物.
- 了解阴离子电荷,溶剂极性和溶剂协调对这些复合物的氧化还原行为的影响.
主要方法:
- 合成具有不同金属离子 (V-Na,V-K,V-Ba,V-La,V-Ce,V-Nd) 的瓦纳迪尔沙兰-皇冠乙烯复合物.
- 使用循环电量计在具有不同介电常数的溶剂 (乙二,DMF,二甲) 中进行电化学分析.
- 溶剂定位研究和结合常数测定溶剂 - 配方体相互作用.
主要成果:
- (V/IV) 的还原潜力在极性较小的溶剂中随着阴离子电荷的增加而无极转移.
- 在DMF中,降低潜力对离子电荷不敏感,这表明溶剂协调主导.
- 增加DMF与皇冠复合体的结合亲和力与增加的阴离子电荷相关,表明易斯酸/基相互作用增强.
- 证据表明,在相关的瓦纳基复合体中,在氧化还原变化时存在弱阴离子结合和解离的证据.
结论:
- 溶剂协调和阴离子/离子效应在调节过渡金属复合物的氧化还原行为方面发挥着重要的,非无害的作用.
- 氧化还原中心周围的局部电场可以通过充电组的功能化进行调整,并受到溶剂相互作用的影响.
- 这些发现为设计具有量身定制的电化学性能的催化剂提供了洞察力.
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