从O2和铜直接形成
J Brannon Gary1, Cooper Citek1, Timothy A Brown1
1Department of Chemistry, Stanford University , Stanford, California 94305, United States.
Journal of the American Chemical Society
|July 29, 2016
概括
铜 (III) 是铜化酶中可行的氧化状态,形成三核和二核产物. 反应性的差异是由于配体的可访问性,而不是氧化能力.
科学领域:
- 生物化学
- 无机化学
- 酶机制
背景情况:
- 铜化酶利用铜的基胺化来激活氧气.
- 由此产生的氧化剂通常被认为是铜 (II) 种.
研究的目的:
- 通过氧化胺结合铜I复合物的过程中直接形成含铜III的产物.
- 在这些系统中研究铜的动力和热力学可行性.
- 探索三核和二核氧化铜物种之间的结构和反应性差异.
主要方法:
- 合成和表征胺结合铜 (I) 复合物.
- 在低温下进行氧化研究.
- 产品形成和反应性的动态分析.
- 进行光谱和结构研究.
主要成果:
- 在氧化基胺-铜复合物中直接证实了铜 (III) 的形成.
- 在低温下确定主要的三核Cu (II) 2Cu (III) O2和二核Cu (III) 2O2物种.
- 在产品分叉之前,证明过氧化物水平的二聚物中间体.
- 三核复合体和二核复合体之间原子反应性的显著差异.
结论:
- 在这些铜氧系统中,铜 (III) 是一种动力学和热力学可访问的氧化状态.
- 组胺配体的结构影响三核和二核氧化铜产物的分布.
- 反应性的差异归因于桥接氧化体配体的可用性,而不是内在氧化强度的变化.
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