O2与瓦纳 (III) 三化物复合物的两步结合,形成一个非瓦纳基瓦纳 (V) 氧复合物
Anthony F Cozzolino1, Daniel Tofan, Christopher C Cummins
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|October 23, 2012
概括
本研究研究了复合物与氧的反应,详细介绍了中间物种的形成及其随后的转化. 该研究还探讨了控制这些反应的方法,从而导致结合的烯酸的氧化.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学
- 反应动力学反应动力学
背景情况:
- 含有庞大的氨基联体的复合物因其独特的反应性而引起人们的兴趣.
- 了解这些复杂物与分子氧的相互作用对于催化和合成应用至关重要.
研究的目的:
- 为了阐明V(N[(t) Bu]Ar) ((3) 与O(2) 的反应途径.
- 描述氧化过程中形成的中间体和产品.
- 调查控制反应结果的策略,特别是抑制不必要的途径.
主要方法:
- 停止流动的动力学研究,以监测反应速率和识别中间体.
- 溶液热量计用于确定热力学参数.
- 计算研究以建模反应机制.
- 用X射线晶体学来确定关键化合物的结构.
主要成果:
- 反应通过一个 η(1) -O(2) 中间体进行,该中间体以 η(2) -O(2) 物种进行异构.
- O(2) 的结合形成 η(2) -O(2) 复合体是高度外热的 (-75.0 ± 2.0 kcal/mol).
- 在 (t) BuCN的存在下,反应产生了所需的 η(2) -O(2) 复合物和氧化化产物,抑制了分解途径.
结论:
- 反应机制涉及不同的中间体,具有不同的氧结合方式.
- 计算和实验数据支持拟议的动力学和热力学概况.
- 添加化物可以有效地重定向反应路径,使新型氧化有机金属化合物的合成成为可能.
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