二次基复合物的α-和β-毒性稳定旋转体之间的平衡
J Jaffart1, M Etienne, F Maseras
1Laboratoire de Chimie de Coordination du CNRS, UPR 8241, 205 Route de Narbonne, 31077 Toulouse Cedex 4, France.
Journal of the American Chemical Society
|June 21, 2001
概括
这项研究表明,的二次基复合物表现出明显的β-毒性和α-毒性结构,其平衡受电子和固体因素的影响. 这些复合物经历热重组,变成线性基复合物.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 化学 化学
背景情况:
- 这项研究研究了含有酸 (TpMe2) 连接体的二次基复合物的结构动力学.
- 了解气体相互作用对于预测有机金属化合物的反应性和稳定性至关重要.
研究的目的:
- 阐明二次基复合物的结构偏好和动态平衡.
- 探索电子和硬体因素对这些系统中的杂态相互作用的影响.
- 描述控制旋转平衡和重排的热力学和动力学参数.
主要方法:
- 用X射线晶体学来确定固态结构.
- 溶液核磁共振 (NMR) 谱学用于研究动态平衡和动力学.
- 混合量子力学/分子力学 (QM/MM) 计算用于理论分析.
主要成果:
- 异烯复合物Tp(Me2) NbCl(i-Pr) ((PhCCMe) 在晶体中表现出β-毒性结构,溶液中的β-和α-毒性旋转体之间存在平衡.
- 在固体和溶液状态下,sec-butyl复合物的二聚体体表现出明显的异体相互作用,其中一个二聚体的平衡值可观察到.
- 核磁共振研究为Nb-C键的平衡和旋转提供了热力学和动力学参数.
- 同位素效应和计算研究证实了硬体和电子因素对气体偏好的影响.
结论:
- 二次基复合物表现出复杂的气动性行为,由电子和固态效应的平衡驱动.
- Tp(Me2) 配体的硬质体质量在指导基组的构成方面发挥着重要作用.
- 所有研究的二次基复合物都经历了热重组,通过一阶过程将其变为线性基复合物.
相关概念视频
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Introduction
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