通过旋转操纵控制反应性:过氧 (III) 复合物的硬体体积
Seonghan Kim1,2, Yuri Lee1, Guilherme L Tripodi3
1Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea.
Journal of the American Chemical Society
|July 20, 2024
概括
在体上的体控制过氧 (III) 复合物的自旋状态,影响它们的反应性. 较大的群体诱导高旋转状态,使氧化成为可能,而较小的群体则有利于低旋转状态,阻碍它.
科学领域:
- 无机化学
- 有机金属化学
- 催化剂
背景情况:
- 过氧 (III) 复合物在氧化反应中至关重要.
- 金属复合物的旋转状态显著影响其反应性.
- 连接体设计是调整金属复杂性质的关键.
研究的目的:
- 研究过氧 (III) 复合物的自旋状态和反应性之间的关系.
- 探索支联体在 (III) 旋转状态上的固态调制的影响.
- 合成和表征具有不同N替代物的新型过氧 (III) 复合物.
主要方法:
- 新型过氧 (III) 复合物的合成和表征.
- 物理化学分析以确定旋转状态.
- 反应性研究,包括亚氧化.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 合成了两种新的过氧 (III) 复合物[CoIII (MDAP) (O2) ]+和[CoIII (ADDAP) (O2) ]+.
- 在控制的旋转状态下 (S=0或S=1) 的体N替代物.
- 含有大量阿达曼/特特基的复合物 (S=1) 氧化了基,而含有甲基的复合物 (S=0) 则没有.
- 由于硬体体积,还氧化潜力与联体场强度相关.
结论:
- 皮里迪诺配体上的N替代物的固体质量是控制氧 (III) 复合物的旋转状态的关键因素.
- 旋转状态决定了这些复合物的反应性,特别是在基激活中.
- DFT计算支持实验结果,强调电子结构的作用.
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