Stabilization of classical (anhydrous) Brønsted acids by the Lewis acids B(C6F5)3 and [Me3Si]+

本研究项目的目的是合成简单的(大多数不稳定的)平面共振稳定的拟卤酸(H-X，X=C(CN)3-，H(CN)NO-，H(CN)NO2-，HC(NO)2-，C(NO2)3-，NC-N-CN-，NC-N-NO2-等)。以及它们的硅烷化同系物(Me3Si-X)，这些化合物在第一阶段尚未被研究。加合物的稳定一方面是通过体积大的中性Lewis酸B(C6F5)3进行的，另一方面是通过非常强的阳离子Lewis酸[Me3Si]+进行的，因此在第一种情况下形成中性酸性加合物(H-X-B(C6F5)3或Me3Si-X-B(C6F5)3)，而与硅离子形成的加合物导致[H-X-SiMe3]+或[Me3Si-X-SiMe3]+的阳离子。这种方法允许系统地研究取决于空间位阻的稳定性、结构和成键(H与Me3Si或B(C6F5)3与。[Me3Si]+)以及加合物体系的电荷(中性与阳离子)。此外，我们还希望将被强电子拉力激活的阴离子用于合成化学中，例如，在亲电取代芳香族化合物中。总而言之，我们想要证明加合物的形成可以用来稳定特别是非常不稳定的平面共振稳定的假卤酸，从而使它们在实质上可用于后续的反应。

The aim of the research project is the synthesis and adduct stabilization of simple (mostly labile) planar, resonance-stabilized pseudohalogen acids (H-X, X = C(CN)3-, H(CN)NO-, H(CN)NO2-, HC(NO)2-, C(NO2)3-, NC-N-CN-, NC-N-NO2-, etc.) as well as their silylated homologues (Me3Si-X), which have not yet been investigated in the first period. Adduct stabilization is to be carried out on the one hand by the bulky, neutral Lewis acid B(C6F5)3 and on the other hand by the very strong cationic Lewis acid [Me3Si]+, so that in the first case neutral acid adducts are formed (H-X-B(C6F5)3 or Me3Si-X-B(C6F5)3), while adduct formation with silylium ions leads to cations of the type [H-X-SiMe3]+ or [Me3Si-X-SiMe3]+. This approach allows the systematic investigation of the stability, structure, and bonding depending on the steric hindrance (H vs. Me3Si or B(C6F5)3 vs. [Me3Si]+) as well as the charge of the adduct system (neutral vs. cationic). Furthermore, we would like to use the anions activated by the strong electron pull in synthetic chemistry, e.g., in electrophilic aromatic substitutions. In summary, we would like to show that adduct formation can be used to stabilize especially the very labile planar resonance-stabilized pseudohaloacids and thus make them accessible in substance for subsequent reactions.