Chemistry of C-Trimethylsilyl-Substituted Main Group Heterocarboranes

该奖项由无机化学、生物无机化学和金属有机化学计划颁发，涉及金属碳化学的一般领域。金属碳硼烷化合物由于它们所展示的不寻常的化学键类型而引起了人们的极大兴趣，而且由于它们是重要陶瓷的前体并且可以用来合成具有有趣的电学性质的新材料，例如一维导体，因此具有重要的实用价值。该项目的主要重点是合成可能具有有趣的结构、电学和光谱性质的扩展主族杂碳硼烷体系。将合成新的主族杂碳硼烷电荷转移络合物，并得到它们的结构。对这些配合物特别感兴趣的是影响顶端杂原子滑移的因素，与顶端杂原子结合的配体的取向，以及配体碱度对团簇成键和结构的影响。还有待探索的是先前关于M(II)插入的闭合和M(IV)夹心的共聚碳硼烷(M=Si和Ge)的工作所提出的新的化学领域。这将包括合成几个多能级堆叠式硅、锗和硅/锗混合夹心络合物，并研究它们的电学性质。杂碳烷化学要探索的最后一个领域是扩展、开发和发展主族杂碳硼烷反应的直接合成方法，其中顶端的杂原子主要与各种主族和过渡金属进行非还原取代反应。

This award from the Inorganic, Bioinorganic and Organometallic Chemistry Program is in the general area of metallacarboranechemistry. Metallacarborane compounds are of substantial current interest because of the unusual types of chemical bonds which they illustrate, and are also of practical importance because they are precursors to important ceramics and can be used to synthesize new materials with interesting electrical properties, such as one-dimensional conductors. The major emphasis of the project is the synthesis of extended main group heterocarborane systems that may exhibit interesting structural, electrical and spectral properties. New charge-transfer complexes of main group heterocarboranes will be synthesized and their structures obtained. Of particular interest for these complexes are the factors which influence the slippage of the apical heteroatom, the orientation of ligands bound to this apical heteroatom, and the effect of ligand basicity on cluster bonding and structure. Also to be explored are new areas of chemistry suggested by previous work on the M(II)-inserted closo- and M(IV)-sandwiched commo-carboranes (M=Si and Ge). This will include the synthesis of several multilevel stacked silicon, germanium and mixed silicon/germanium sandwiched complexes and a study of their electrical properties. The final area of heterocarborane chemistry to be explored is direct synthetic approaches to extend, exploit and develop reactions of main group heterocarboranes in which the apical heteroatom undergoes predominantly nonreductive substitution reactions with a variety of main group and transition metals.