对于16和17电子有机金属反应中间体的TEMPO反应性:一个时间解析的IR研究
Justin P Lomont1, Son C Nguyen, Charles B Harris
1Department of Chemistry, University of California, Berkeley, Berkeley 94720, California, USA.
Journal of the American Chemical Society
|July 4, 2013
概括
这种 (2,2,6,6-四甲基利丁-1-) 氧基 (TEMPO) 与不和的有机金属中间体发生反应. 时光作为一个阳离子连接体,通过一个关联机制协调和氧化金属中心.
科学领域:
- 有机金属化学 有机金属化学
- 频谱学是一种光谱学.
- 计算化学的计算化学
背景情况:
- 在催化和生物研究中, (2,2,6,6-四甲基胺-1-) 氧基 (TEMPO) 是多功能性的.
- 在有机金属复合体中作为连接体时,TEMPO表现出多种协调模式.
研究的目的:
- 研究TEMPO与协调不和的16和17电子有机金属反应中间体的反应性.
- 描述TEMPO对金属中心的协调机制.
主要方法:
- 超快速的时间分辨率红外光谱学用于监测反应.
- 密度函数理论 (DFT) 计算以解释光谱和分析结构.
主要成果:
- 通过一个关联机制,TEMPO 坐标为 16 电子 (CpCo (((CO),Fe (((CO) 4) 和 17 电子 (CpFe (((CO) 2 ,Mn (((CO)) 5) 的物种.
- 时间引证显示,时间作为具有金字塔式气几何形状的阳离子联体起作用.
- 金属中心在TEMPO协调时被氧化.
结论:
- 这项研究提供了TEMPO与不和有机金属复合物的反应机制的第一个直接表征.
- 结果为TEMPO与常见反应中间体的相互作用提供了有价值的见解.
- 在研究的各种低价值过渡金属复合物中,TEMPO的反应性是一致的.
相关概念视频
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