BX ((3) 和CX ((3) ((+) 的水添加物:对结构,结合和反应性的影响
1Universität Karlsruhe, Engesserstrasse Geb. 30.45, D-76128 Karlsruhe, Germany. krossing@chemie.uni-karlsruhe.de
Journal of the American Chemical Society
|June 17, 2004
概括
计算化学揭示了 (BX(3) 和碳 (CX(3) ((+)) 化合物的水添加物的独特结构. 复合物表现出强大的B-O键,而碳添加物则有利于较弱的C-X pi键,影响反应机制.
科学领域:
- 计算化学的计算化学
- 量子化学 是一个量子化学.
- 无机化学 无机化学
背景情况:
- 三化物 (BX(3) 和三甲基离子 (CX(3) ((+)) 的水添加物具有截然不同的结构特征.
- 以前的研究可能低估了由于计算局限性的结构差异.
研究的目的:
- 阐明由BX(3) 和CX(3) ((+) 种形成的水添加物的独特结构性质.
- 调查pi-bonding在确定这些引证的结构中的作用.
- 以更高的准确性重新评估早期的计算发现.
主要方法:
- 高质量的初始计算,特别是MP2 (MøllerPlesset扰动理论).
- 使用灵活的基础集 (例如,TZVPP) 来准确地描述潜在能量表面 (PES).
主要成果:
- 复合物采用经典的Cs对称结构,具有强大的B-O键和键.
- 较重的CX(3)(+) 阴离子 (X=Cl-I) 形成非经典的,弱结合的添加物,最大限度地增加C-X pi结合.
- 阳性电荷转移增强了酸 (BX(2) ((+) 中的pi键,缩短了B-X键.
结论:
- 对于pi键形成的驱动力在BX(3) 和CX(3) ((+) 系统之间存在显著差异.
- 准确的计算方法对于正确表征这些弱键附加物至关重要.
- 非经典的引证表明有机化学中的素协调涉及潜在的反应机制.
相关概念视频
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