AN Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russia.
J Phys Chem A. 2011 Nov 17;115(45):12738-45. doi: 10.1021/jp203730b. Epub 2011 Sep 1.
The conformational effects in bicyclo[3.3.1]nonanes, while thoroughly studied, have not yet received the full theoretical explanation. R. F. W. Bader's quantum theory of atoms in molecules presents unique opportunities for studying the stereoelectronic interactions (SEI) and weak intramolecular bonding leading to these effects. Here, we report the study of 3,7-dithia-1,5-diazabicyclo[3.3.1]nonane by means of the topological analysis of the calculated (MP2(full)/6-311++G**) and experimental (X-ray derived) charge density to reveal the origins of the so-called "hockey sticks" effect observed in similar compounds. A new explanation of the relative stability of bicyclo[3.3.1]nonane conformers based on the analysis of the QTAIM atomic energies is given. The H···H and S···S interactions in bicyclo[3.3.1]nonane and its dithia derivatives are shown to be significant factors contributing to the differences in the relative stability of the conformers.
双环[3.3.1]壬烷的构象效应虽然已经得到了深入研究，但尚未得到全面的理论解释。R. F. W. Bader 的分子中的原子量子理论为研究导致这些效应的立体电子相互作用（SEI）和弱分子内键提供了独特的机会。在这里，我们通过拓扑分析计算（MP2（全）/6-311++G**）和实验（X 射线衍生）电荷密度来研究 3,7-二硫代-1,5-二氮杂双环[3.3.1]壬烷，以揭示在类似化合物中观察到的所谓“曲棍球棒”效应的起源。基于 QTAIM 原子能量分析，给出了双环[3.3.1]壬烷构象异构体相对稳定性的新解释。双环[3.3.1]壬烷及其二硫代衍生物中的 H···H 和 S···S 相互作用被证明是影响构象异构体相对稳定性差异的重要因素。
