两个坐标的d9复合体.两个坐标的d9复合体. 合成和氧化NHC ((I) 胺基的合成和氧化
Carl A Laskowski1, Gregory L Hillhouse
1Gordon Center for Integrative Science, Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, USA.
Journal of the American Chemical Society
|September 27, 2008
概括
合成了新型 ((I) 复合物与体积庞大的配体. 这些复合物经历氧化和重新排列反应,产生独特的伊米诺西兰和二度结构,扩展有机化学.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂 催化剂
- 协调化学 协调化学
背景情况:
- 低坐标复合物是催化过程中至关重要的中间体.
- 了解它们的反应性为我们提供了关于催化循环的见解.
- 硬质要求高的连接物影响复合物的稳定性和反应性.
研究的目的:
- 合成和表征新的单体,二坐标Ni (I) 复合体.
- 研究这些Ni(I) 复合物的氧化反应活性.
- 为了探索不同寻常的含结构的形成.
主要方法:
- 合成 (I) 复合物从 (I) 二聚物和体胺/化物联体.
- 合成的 (I) 复合物的电化学氧化.
- 使用光谱技术和X射线晶体学 (隐含) 进行产品的表征.
主要成果:
- 成功合成了单质,二坐标的Ni (I) 复合物: (IPr) Ni{N (SiMe3) 2} (2) 和 (IPr) Ni (NHAr) (3).
- 复合物2的氧化导致β-Me的消除,形成一个基稳定型的伊米诺西兰复合物[(IPr) Ni(CH3) {kappa1-N(SiMe3) =SiMe2.Et2O}][BArF4] (6).
- 复合体3的氧化产生了阴离子3协调复合体 (4),在THF损失时重新排列为二次结构 (5).
结论:
- 证明了新型2坐标Ni(I) 复合物与重的N-异环碳素 (IPr) 配体的可访问性.
- 揭示了独特的反应途径,包括在单电子氧化时的β-Me消除和连接体重组.
- 扩大了有机化学的范围,形成了前所未有的 iminosilane 和二度物种.
相关概念视频
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