具有竞争力的碳-硫与碳-碳键激活2-cyanothiophene与[Ni(dippe) H]2的竞争性碳-硫与碳-碳键激活
Matthew R Grochowski1, Ting Li, William W Brennessel
1Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
Journal of the American Chemical Society
|August 14, 2010
概括
这项研究使用化合物研究了C-C和C-S键裂变. 研究人员确定了关键的中间体和产品,揭示了对有机金属反应机制的洞察力.
科学领域:
- 有机金属化学 有机金属化学
- 一致性催化剂的同质性
- 反应机制 解 反应机制
背景情况:
- 了解有机金属化合物中的键裂解对于催化是至关重要的.
- 复合物与硫衍生物的反应性尚未完全理解.
研究的目的:
- 为了研究一个特定的同质有机金属化合物的C-C和C-S键裂解路径,[Ni(dippe) H](2).
- 为了描述与2-cyanothiophene反应过程中形成的中间体和产品.
- 用实验和理论方法阐明反应机制.
主要方法:
- [Ni(dippe) H](2) 与2-cyanothiophene 的反应.
- 使用NMR光谱和X射线衍射对产品进行表征.
- 低温 (31) P 核磁共振光谱法用于观察中间体.
- 独立合成,理论计算 (DFT) 和化学表征.
主要成果:
- 酸替代C-S键的裂变形成了一个Ni-金属循环复合物 (2a).
- 加热2a导致C-CN键裂变,产生产品 (3).
- 鉴定了一种非替代C-S键裂变的动力产物 (2b),一种Ni(0) 乙二二烯酸中间体 (4),以及一种双核Ni(0) -Ni(II) 产物 (6b).
- DFT分析提供了债券分拆过渡状态的比较细节.
结论:
- 反应通过不同的C-S和C-CN键裂解路径进行.
- 确定了多种中间体和产物,突出显示了反应的复杂性.
- 这项研究提供了对介导的烯功能化的全面机制理解.
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