Organosilicon Molecular Assembly, Synthesis, and Electron Transfer

该提案描述了几个涉及含硅有机分子的问题，硅是元素周期表中仅次于碳的原子。硅的存在提供了几个优点，事实上，是所有这些问题的关键组成部分。首先，硅氧键的高强度使复杂分子能够自组装。具有纳米尺寸空腔的大环被设计成充当宿主。Si-O键的分子识别将证明有机硅化合物可以具有有趣且有用的水化学。一种新的试剂家族将对反应性进行控制，从而有利于单一镜像产物（对映选择性）。其次，硅被用来构建新的分子球形和半球形腔。环糊精和杯芳烃将连接到有机硅酸盐网络，以制备能够与小分子结合的微孔结构。一个全新的腔包含系统，来自中央硅原子将被准备。第三，电子转移将被表征为沿着全硅分子骨架，即硅线。这项研究将是第一次尝试表征基于完全非碳途径的分子大小的电线。第四，将制备新的系统，其中硅带正电荷，并且仅连接到三个其他基团（硅阳离子）。第五，硅试剂将用于在室温下制备含有带正电荷的碳（碳阳离子）的新体系。有了这个更新奖，有机和大分子化学计划正在支持约瑟夫B博士的研究。西北大学化学系的兰伯特说。Lambert教授将把工作重点放在将硅纳入碳化合物的正常类似物或新结构中，以创造具有潜在重要性质的分子。这些性质可能具有理论意义，也可能提供新的实际应用。通过利用其中一种反应来设计一种新的方法，在催化过程中将硅-氢键添加到碳-碳双键（氢化硅烷化）中，但避免使用当前过程中所需的贵金属，从而扩大了该项目的范围。

This proposal describes several problems that involve organic molecules containing silicon, the atom just below carbon in the periodic table. The presence of silicon offers several advantages and, in fact, is the key component of all these problems. First, the high strength of the silicon-oxygen bond enables complex molecules to be self-assembled. Large rings with nanometer-sized cavities are designed to serve as hosts. Molecular recognition of the Si-O bond will demonstrate that organic-silicon compounds can have an interesting and useful aqueous chemistry. A new family of reagents will exert control on reactivity so that a single mirror image product is favored (enantioselectivity). Second, silicon is used to construct new molecular spherical and hemispherical cavities. Cyclodextrins and calixarenes will be attached to an organosilicate network to prepare microporous structures capable of binding with small molecules. An entirely new cavity-containing system that derives from a central silicon atom will be prepared. Third, electron transfer will be characterized along an all-silicon molecular backbone, that is, a silicon wire. This study will be the first attempt to characterize a molecular-sized wire based on an entirely non-carbon pathway. Fourth, new systems will be prepared in which silicon is positively charged and attached to only three other groups (silylium cations). And, fifth, silicon reagents will be used to prepare, at room temperature, new systems containing positively charged carbon (carbocations).With this renewal award, the Organic and Macromolecular Chemistry Program is supporting the research of Dr. Joseph B. Lambert of the Department of Chemistry at Northwestern University. Professor Lambert will focus his work on incorporating silicon into normal analogues of carbon compounds or into novel structures to create molecules with potentially important properties. The properties may be of theoretical interest or they may offer new practical applications. The scope of the project is increased by exploiting one of the reactions to devise a new method to add the silicon-hydrogen bond to carbon-carbon double bonds (hydrosilylation) in a process that is catalytic but avoids the use of precious metals necessary in the current process.