Department of Chemistry and Biochemistry, University of Mississippi, 322 Coulter Hall, University, MS 38677-1848, USA.
Chemistry Department, Central Alabama Community College, 1675 Cherokee Road, Alexander City, AL 35010, USA.
Molecules. 2019 Jul 10;24(14):2523. doi: 10.3390/molecules24142523.
A recent computational analysis of the stabilizing intramolecular OH⋯O contact in 1,2-dialkyl-2,3-epoxycyclopentanol diastereomers has been extended to thiiriane, aziridine and phosphirane analogues. Density functional theory (DFT), second-order Møller-Plesset perturbation theory (MP2) and CCSD(T) coupled-cluster computations with simple methyl and ethyl substituents indicate that electronic energies of the c i s isomers are lowered by roughly 3 to 4 kcal mol when the OH group of these cyclopentanol systems forms an intramolecular contact with the O, S, N or P atom on the adjacent carbon. The results also suggest that S and P can participate in these stabilizing intramolecular interactions as effectively as O and N in constrained molecular environments. The stabilizing intramolecular OH⋯O, OH⋯S, OH⋯N and OH⋯P contacts also increase the covalent OH bond length and significantly decrease the OH stretching vibrational frequency in every system with shifts typically on the order of -41 cm.
最近对 1,2-二烷基-2,3-环氧环戊醇非对映异构体中稳定的分子内 OH⋯O 接触的计算分析已经扩展到了硫杂环丙烯、氮杂环丙烷和膦杂环丙烷类似物。密度泛函理论（DFT）、二级Møller-Plesset 微扰理论（MP2）和简单甲基和乙基取代基的 CCSD(T)耦合簇计算表明，当这些环戊醇系统中的 OH 基团与相邻碳原子上的 O、S、N 或 P 原子形成分子内接触时，c i s 异构体的电子能大约降低 3 到 4 kcal mol。结果还表明，在约束分子环境中，S 和 P 可以像 O 和 N 一样有效地参与这些稳定的分子内相互作用。在每个体系中，稳定的分子内 OH⋯O、OH⋯S、OH⋯N 和 OH⋯P 接触还增加了共价 OH 键长，并显著降低了 OH 伸缩振动频率，每个体系的位移通常在-41 cm 左右。
