H(2) 进化机制来自光生成的基多科巴洛克西姆
Jillian L Dempsey1, Jay R Winkler, Harry B Gray
1Beckman Institute, California Institute of Technology, Pasadena, California 91125, United States.
Journal of the American Chemical Society
|November 12, 2010
概括
这项研究详细介绍了从激发的化石到复合物的质子转移,从而迅速形成了Co (III) H. 随后的还原和质子化产生气,阐明了催化反应中的关键步骤.
科学领域:
- 摄影化学的使用.
- 无机化学 无机化学
- 催化剂是一种催化剂.
背景情况:
- 二氧化复合体是已知的催化剂.
- 了解激发状态质子转移对于催化机制至关重要.
研究的目的:
- 研究从激发光酸转移到复合物的质子转移机制.
- 量化中间体形成和随后反应的动力学.
主要方法:
- 用过渡吸收光谱来监测反应.
- 进行了动力分析以确定速率常数.
主要成果:
- 从三重激发的化醇到Co(I) - diglyoxime的质子转移迅速发生 (3.5-4.7 × 10^9 M−1 s−1).
- 介质Co(III) H被过多的Co(I) -diglyoxime (k_red = 9.2 × 10^6 M−1 s−1) 减少了.
- 最终产品是二氧化和H2气体.
结论:
- 质子转移与光酸的兴奋状态失活相结合.
- 反应通过不同的中间物种进行,Co (III) H和Co (II) H.
- 这项工作为介导的生产途径提供了详细的动力洞察.
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