一种高度稳定的N-异环碳复合物,由三-氧- ((V) 组成,表现出新的Cl-C碳结合相互作用
Colin D Abernethy1, Gareth M Codd, Mark D Spicer
1Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, Scotland G1 1XL, United Kingdom. colin.abernethy@strath.ac.uk
Journal of the American Chemical Society
|January 30, 2003
概括
N-异环碳稳定了高氧化状态的复合物. 化物联体和碳烯之间的新型结合相互作用.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- N-异环碳 (NHCs) 是有机金属化学中的多功能联体.
- 在高氧化状态下稳定金属复合物仍然是一个重大挑战.
- 以前对NHC结合的理解主要涉及向金属中心的西格玛捐赠.
研究的目的:
- 探索NHCs在稳定高氧化状态金属复合物的实用性.
- 为了研究NHC和 (V) 复合体之间形成的添加物的结构和电子特性.
- 为了阐明这种新类化合物中存在的结合相互作用.
主要方法:
- 在1,3-dimesitylimidazol-2-ylidene和三-oxo-vanadium (V) 之间合成1:1的添加物.
- 进行X射线晶体学以确定 adduct 的分子结构.
- 密度函数理论 (DFT) 计算来分析结合相互作用.
主要成果:
- 一个NHC和的稳定于空气的1:1附加物{V}被成功合成.
- 结构分析揭示了cis-化物连接体对碳基碳的独特方向.
- DFT计算确定了化物单一对和基的正式空置的p轨道之间的结合相互作用.
结论:
- N-异环碳可以有效地稳定高氧化状态的金属复合物.
- 对NHCs发现了一种新的结合模式,涉及与金属结合联体的相互作用.
- 这一发现扩大了对NHC连接体行为的理解,并为协调化学开辟了新的途径.
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