An efficient computational approach for the evaluation of substituent constants
An efficient computational approach for the evaluation of substituent constants
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DOI：
10.1021/jo0605288
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发表时间：
2006-08-18
影响因子：
3.6
通讯作者：
Schaefer, Henry F., III
中科院分区：
文献类型：
--
作者：
Galabov, Boris;Ilieva, Sonia;Schaefer, Henry F., III
在B3 LYP/6-311+G（2d，2 p）和BPW 91/6- 311 G（d，p）水平上对15个单取代苯衍生物进行了密度泛函理论计算，研究了电子结构参数与实验反应性常数之间的关系.本文介绍了一种计算取代苯体系σ（0）取代基常数的有效而精确的方法。它是基于实验反应常数和理论静电势值（EPN）在帕拉和Meta位的碳原子之间的良好的线性相关性。结果强调了EPN作为局部反应性描述符的有用性。使用SCIPCM方法评估水溶剂的影响的理论计算表明，溶剂将极性取代基的总体效果提高约30%。所得结果还表明，σ（0）常数的相对值主要是由分子内的影响。
Density functional theory computations at the B3LYP/6-311+G(2d, 2p) and BPW91/6-311G(d, p) levels were carried out for a series of 15 monosubstituted benzene derivatives to study dependencies between electronic structure parameters and experimental reactivity constants. An efficient and accurate computational approach for the evaluation of sigma(0) substituent constants for substituted benzene systems is outlined. It is based on the excellent linear correlation between the experimental reactivity constants and the theoretical electrostatic potential values (EPN) at the carbon atoms in the para and meta positions. The results underline the usefulness of the EPN as a local reactivity descriptor. Theoretical computations to assess the influence of water solvent using the SCIPCM method showed that the solvent enhances the overall effect of polar substituents by about 30%. The results obtained indicate also that the relative values of the sigma(0) constants are predominantly determined by intramolecular influences.