Structure and Reactivity of 1,8-Bis(naphthalenediyl)dipnictanes

Syntheses and solid-state structures of diarsane Naph2As2 (Naph = 1,8-naphthalenediyl, 1) and (Naph)5Sb4Cl2 3 are reported and the σ-donor capacity of Naph2E2 (E = As 1, Sb 2) was studied in reactions with (coe)­Cr­(CO)5 (coe = Z-cyclooctene), yielding [Naph2As2]­[Cr­(CO)5]2 (4) and [Naph2E2]­[Cr­(CO)5] (E = As 5, Sb 6). In contrast, reactions of 1 and 3 with Me2SAuCl proceed with oxidation and formation of elemental gold as well as Naph2(AsCl)2 (7) and [NaphSbCl2]2 8. All complexes were characterized by elemental analyses, heteronuclear (1H, 13C) NMR and FT-IR spectroscopy, as well as single crystal X-ray diffraction. Intermolecular E···π interactions (E = As, Sb), which were observed in 7 and 8, were quantified by use of density functional theory and local coupled cluster electronic structure theory calculations. These allow to assess the nature and relative importance of covalent and noncovalent interactions and illustrate how dispersion interactions change with the electronic structure of the compounds.本文报道了二胂类化合物Naph₂As₂（其中Naph=1,8-萘二基，记为1）以及(Naph)₅Sb₄Cl₂（记为3）的合成与固态结构。本文还研究了Naph₂E₂（E=As，记为1；E=Sb，记为2）的σ给体（σ-donor）能力，通过其与(coe)Cr(CO)₅（其中coe为Z-环辛烯）的反应进行考察，最终得到产物[Naph₂As₂][Cr(CO)₅]₂（记为4）以及[Naph₂E₂][Cr(CO)₅]（E=As记为5，E=Sb记为6）。与之不同，化合物1与3分别与Me₂SAuCl发生反应时，会伴随氧化过程，生成单质金，同时得到Naph₂(AsCl)₂（记为7）以及[NaphSbCl₂]₂（记为8）。所有配合物均通过元素分析、异核（¹H、¹³C）核磁共振波谱、傅里叶变换红外（FT-IR）光谱以及单晶X射线衍射进行了表征。在化合物7和8中观测到的分子间E···π相互作用（E=As、Sb），通过密度泛函理论（density functional theory）与局域耦合簇电子结构理论（local coupled cluster electronic structure theory）计算进行了定量分析。这些计算结果可用于评估共价与非共价相互作用的本质及其相对重要性，并阐明色散相互作用如何随化合物的电子结构发生变化。