内分子结增强单核超氧化物复合物的稳定性和反应性
Mayukh Bhadra1, Jung Yoon C Lee1, Ryan E Cowley2
1Department of Chemistry , The Johns Hopkins University , Baltimore , Maryland 21218 , United States.
Journal of the American Chemical Society
|June 30, 2018
概括
铜-超氧复合物是氧化过程中的关键中间体. 内分子键稳定这些复合物,并增强它们在原子抽象反应中的反应性.
科学领域:
- 生物有机化学
- 氧化化学
- 协调化学
背景情况:
- 铜-超氧复合物是铜介导的氧化生化过程中的关键反应中间体.
- 这些中间体在基甘氨酸α-氧化单酶 (PHM) 和多巴胺β-氧化酶 (DβM) 等酶中起着重要的作用.
研究的目的:
- 稳定和系统地研究LCuII复合体.
- 研究分子内键对这些铜-超氧中间体的稳定性和反应性的影响.
- 探索连体结能力与铜-超和铜-化合物的光谱性质之间的关系.
主要方法:
- 使用TMPA连接体框架合成和稳定铜-超氧复合物.
- 系统地修改由连接体衍生的键.
- 铜-超和铜-类的光谱特征.
- 对原子抽象 (HAA) 的O-H键的反应性的评估.
主要成果:
- 在TMPA连接体框架内的分子内键成功稳定了[L) CuIIO2•-) +复合体.
- 随着基衍生结的逐渐增强,铜-超氧复合物对基O-H键的HAA的反应性显著提高.
- 对超氧复合物和亚复合物观察到光谱性质的系统性变化,与连接物结合能力相关.
结论:
- 内分子键是稳定关键铜-超氧中间体的有效策略.
- 结合可调节的结相互作用的连接体设计可以调节氧化过程中的铜复合物的反应性.
- 这项工作为铜催化氧化反应的机制提供了基本的见解.
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