在 (III) -超氧复合物的质子合电子转移反应中显著的酸催化
Tarali Devi1, Yong-Min Lee1, Wonwoo Nam1,2
1Department of Chemistry and Nano Science , Ewha Womans University , Seoul 03760 , Korea.
Journal of the American Chemical Society
|June 28, 2018
概括
在氧原子转移反应中,三酸显著增强了酸催化作用. 这种由质子-合电子转移解释的质子效应加快了反应速率的1万倍.
科学领域:
- 无机化学
- 催化剂
- 反应机制
背景情况:
- 单核非血Cr (III) -超氧复合物是氧化反应中的关键中间体.
- 对于催化剂设计来说,了解外部因素如酸对这些复合物的影响至关重要.
研究的目的:
- 为了研究三叶酸对单核非血III-超复合物的氧原子转移 (OAT) 反应性的作用.
- 阐明观察到的反应性增强背后的机制.
主要方法:
- 使用了一种单核非血Cr (III) -超氧复合物, [ (Cl) (TMC) Cr (III) (O2) ]+ (1).
- 在三叶酸 (HOTf) 存在或不存在的情况下进行OAT反应.
- 研究了电子转移 (ET) 动力学,使用像铁素这样的电子捐赠者,并应用了马库斯理论.
主要成果:
- 观察到OAT反应的酸催化显著增强,速度加快了10^4倍.
- 证明从捐赠体到Cr (III) -超氧复合体的电子转移仅在HOTf的存在下发生.
- 通过质子合电子转移 (PCET) 机制解释了增强的反应性.
结论:
- 在OAT反应中,三酸显著增强了单核非血Cr (III) - 超复合物的催化活性.
- 这项研究首次证实了对金属超物种化学性能的显著质子影响.
- 这些发现突显了质子合电子转移在调节这些重要的催化中间体的重要性.
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