New Aspect of Tetrahedrane : Synthesis and Properties of Highly Strained σ-π Condugated Molecules

四面烷是一种碳氢化合物，具有高度紧张的碳-碳σ键。由于骨架的高度应变，C-Cσ键轨道能级的增加导致了四面体σ-π框架与相邻的σ轨道体系之间的π共轭。我们研究了全氟芳基取代四面体的合成、结构分析和性质。到目前为止，还没有关于硫取代四面体等稳定杂原子的报道。报道了二苯基二硫醚与四面体锂通过亲核取代反应制备的苯硫基四面体的合成、结构和性质。用核磁共振和X-射线单晶衍射法对所合成的四面体进行了结构表征。在全氟芳基取代四面体的UV-Vis光谱测量中，观察到相对于未取代的全氟苯有明显的红移。结果表明，四面体σ-π框架与全氟芳基σ-体系发生了扩展的π共轭。

Tetrahedrane is a hydrocarbon with highly strained carbon-carbon σ bonds. Because of the extremely strained skeleton, the increase in the energy level of C-C σ-bond orbitals results in the σ-π conjugation between tetrahedrane σ-frame with adjacent π-orbital system. We have investigated the synthesis, structural analysis and properties of perfluoroaryl substituted tetrahedranes. Up to now, there is also no report of stable heteroatom such as sulfur substituted tetrahedranes. We report the synthesis, structure and properties of phenylthio tetrahedranes which was prepared by the nucleophilic substitution of diphenyldisulfide and tetrahedranyllithim. Our tetrahedranes were fully characterized by NMR and X-ray crystallography. On the measurement of UV-vis spectrum of perfluoroaryl substituted tetrahedranes, a significant bathochromic shift relative to the non-substituted perfluorobenzene was observed. It indicate the extended σ-π conjugation of tetrahedrane σ-frame and perfluoroaryl π-system.