alpha-Acidities of conformationally constrained sulfides, sulfoxides and sulfones

了解化合物的结构性质和稳定性对于理解化合物的反应性至关重要，并将有助于开发新的合成方法。化合物的反应性（除其他外）在很大程度上受其酸度的支配。我们将通过测量和量子化学计算来确定硫化物、亚砜和砜的酸度，并将揭示这些酸度的原因。利用构象约束底物，我们将能够确定，哪个影响来自于官能团相对于各自的酸性质子的取向。这些知识与立体选择反应的发展尤其相关。这些构象约束化合物的合成是这个项目的一部分；我们计划重点研究1,3-二thiane和2-thiaadamantane衍生物。我们将优化和使用现有的方法，在紫外线指示剂存在的情况下，通过滴定来测量酸度。酸度将使用DFT方法计算；它们将用自然键轨道（NBO）和等地计算来合理化。

Knowledge of structural properties and stabilities of chemical compounds is essential for the understanding of the compound´s reactivities and would allow for the development of new synthetic methods. The reactivity of chemical compounds is significantly ruled (inter alia) by their acidities. We will determine the acidities of sulfides, sulfoxides, and sulfones by measurement and by quantum chemical calculations and will reveal the reasons for these acidities. By utilization of conformationally constrained substrates we will be able to determine, which influence comes from an orientation of the functional groups relative to the respective acidic protons. This knowledge is especially relevant for the development of stereoselective reactions. The synthesis of these conformationally constrained compounds is part of this project; we plan to focus on 1,3-dithiane and 2-thiaadamantane derivatives. We will optimize and use an existing method for the measurement of the acidities based on a titration in the presence of UV indicators. The acidities will be calculated using DFT methods; they will be rationalized with natural bond orbital (NBO) and isodesmic calculations.