College of Chemical Engineering, Northwest University for Nationalities, Lanzhou, Gansu 730030, China.
J Mol Model. 2013 Apr;19(4):1739-50. doi: 10.1007/s00894-012-1736-1. Epub 2013 Jan 8.
Gas-phase reactions of ClO(-)/BrO(-) with RCl (R = CH₃, C₂H₅, and C₃H₇) have been investigated in detail using the popular DFT functional BHandHLYP/aug-cc-pVDZ level of theory. As a result, our findings strongly suggest that the type of reaction is firstly initiated by a typical SN2 fashion. Subsequently, two competitive substitution steps, named as SN2-induced substitution and SN2-induced elimination, respectively, would proceed before the initial SN2 product ion-dipole complex separates, in which the former exhibits less reactivity than the latter. Those are consistent with relevant experimental results. Moreover, we have also explored reactivity difference for the title reactions in term of some factors derived from methyl group, p-π electronic conjugation, ionization energy (IE), as well as molecular orbital (MO) analysis.
采用密度泛函理论中的 BHandHLYP/aug-cc-pVDZ 水平,详细研究了 ClO(-)/BrO(-)与 RCl(R = CH₃、C₂H₅和 C₃H₇)在气相中的反应。结果表明,反应类型首先由典型的 SN2 方式引发。随后,在初始 SN2 产物离子-偶极复合物分离之前,分别进行两个竞争性取代步骤,分别称为 SN2 诱导取代和 SN2 诱导消除,其中前者的反应性低于后者。这些结果与相关的实验结果一致。此外,我们还从甲基、p-π 电子共轭、电离能(IE)以及分子轨道(MO)分析等方面探讨了标题反应的反应性差异。