通过9组双金属化物复合物对O2减量的机制研究
Thomas S Teets1, Daniel G Nocera
1Department of Chemistry, 6-335, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, United States.
Journal of the American Chemical Society
|September 22, 2011
概括
合成和动力学研究揭示了由迪罗复合体减少氧气到水中的机械细节. 过氧化物和氧化物中间体在这个过程中至关重要,正如对迪罗和迪里复合物的研究所证明的那样.
科学领域:
- 无机化学 无机化学 有机化学
- 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:
- 迪罗复合物正在研究它们在氧气减少到水中的作用.
- 了解这些反应的机制对于开发高效的催化系统至关重要.
研究的目的:
- 为了阐明由迪罗和迪里复合体介导的O(2) 降解为水的机械路径.
- 确定触媒循环中涉及的关键中间体和反应步骤.
主要方法:
- 混合价值二和二复合物的合成和表征.
- 质子化研究以形成化物复合物.
- 对与O(2) 和HCl.Cl.反应的动力学研究.
- 隔离中间体的光谱和结构分析.
主要成果:
- 迪罗复合物1的质子化产生了Rh(2)(II,II) 化物复合物2,它调解了O(2) 减少.
- 化物复合物4被质子化形成可分离的化物复合物5,与O(2) 反应形成过氧化物复合物6.
- 复合物4还形成了一个 η(2) -氧化物复合物7,在质子化后产生了6.
- 动力学研究支持和系统的HCl消除机制,对观察到额外的途径.
结论:
- 过氧化物和氧化物中间体在由二化物复合体将O2降解为水中发挥着重要作用.
- 机械的途径包括HCl的消除,直接的O(2) 插入和单分子异构.
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