Studies on the Synthesis, Structures, Properties and Functions of Aromatic Compounds Containing Heavier Group 14 Elements

目前还没有稳定的、中性的、含有较重的14族元素的杂芳烃化合物，它们的结构和性质也尚未被揭示。本课题利用有效的空间保护基团2，4，6-三[双(三甲基硅基)甲基]苯基和2，6-bis[bis(trimethylsilyl)methyl]-4-[tris(trimethylsilyl)methyl]phenyl(BBT)，研究了新型含重14族元素的杂芳烃的合成，并阐明了它们的结构和性质。利用TBT和BBT基团，我们成功地合成并分离出了第一个稳定的硅苯、1-硅菲、2-硅菲、9-硅杂菲、9-硅菲、Germabenzen、2-Germanáen和9-germaanthene。X-射线结构分析、核磁共振光谱、UV/Vis和拉曼光谱数据以及理论计算表明，这些化合物均为芳香族化合物以及相应的碳类似物。结果表明，这些化合物与H_2O、MeOH等发生了向Si=C或Ge=C双键的1，2-或1，4-加成反应。有趣的是，发现六族金属(铬、钼、钨)与六价金属形成了η^6-金属苯芳烃络合物。我们认为，这一新的认识为含有较重的14族元素的杂环化合物的化学奠定了基础。我们期待在这些结果的基础上，揭示含有较重的14族元素的杂芳族化合物的新的性质和功能，显示出潜在的适用性。这种化学不仅将应用于新型功能化合物的合成，还将应用于新型催化。

There has been no stable, neutral heteraaromatic compounds containing heavier group 14 elements, and their structures and properties have not been revealed yet. In this project, we studied on the synthesis of new type of heteraaromatic compounds containing a heavier group 14 element by taking advantage of effective steric protection group, 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl (Tbt) and 2,6-bis[bis(trimethylsilyl)methyl]-4-[tris(trimethylsilyl)methyl]phenyl (Bbt) and elucidated their sturctures and properties. Based on these results, we revealed the aromaticity of these compounds.We succeeded in the synthesis and isolation of the first stable silabenzene, 1-silanaphthalene, 2-silanaphthalene, 9-silaanthracene, 9-silaphenanthrene, germabenzene, 2-germanaphthalene, and 9-germaanthracene as stable crystals by taking advantage of Tbt and Bbt groups. The X-ray structural analyses, spectral data on NMR, UV/vis, and Raman spectroscopy, and theoretical calculations indicated that all these compounds are aromatic compounds as well as the corresponding carbon analogues. It was elucidated that these compounds underwent ready 1,2-or 1,4-addition towards the Si=C or Ge=C double-bond with H_2O, MeOH, and so on. Interestingly, the sila-and germabenzene were found to form the η^6-metallabenzene arene complexes with group 6 metals (Cr,Mo,and W).We think that the new knowledge obtained in this project lays the foundations of the chemistry of heteraaromatic compounds containing heavier group 14 elements. We expect that novel properties and functions of heteraaromatic compounds containing heavier group 14 elements will be revealed on the basis of these results, showing the potential applicability. Such chemistry will be applied to not only the synthesis of novel functional compounds but also the novel catalysis.