Organosilicon Molecular Assembly, Synthesis, and Electron Transfer

有机硅分子组装、合成和电子转移

• 批准号: 0091162
• 负责人: Joseph Lambert
• 金额: $ 43.78万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-04-15 至 2004-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0091162&HistoricalAwards=false
• 关键词: Organosilicon; Molecular; Assembly; Synthesis; Electron

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.

这项提议描述了几个涉及含有硅的有机分子的问题，硅原子在元素周期表中仅次于碳。硅的存在提供了几个优点，事实上，它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的分子能够自组装。带有纳米大小空腔的大环被设计为主机。硅-氧键的分子识别将证明有机硅化合物可以具有有趣和有用的水化学。一种新的试剂家族将对反应活性施加控制，从而有利于单一镜像产品(对映体选择性)。其次，硅被用来构建新的分子球形和半球形空腔。环糊精和杯芳烃将被连接到有机硅酸盐网络上，以制备能够与小分子结合的微孔结构。一种由中心硅原子衍生的全新的腔体系统将被制备出来。第三，电子转移将沿着全硅分子骨架，即硅线来表征。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导线。第四，将准备新的体系，其中硅带正电荷，并且只与其他三个基团(硅阳离子)相连。第五，硅试剂将被用来在室温下制备含有正电荷碳(碳正离子)的新体系。有了这个续展奖，有机和高分子化学计划将支持西北大学化学系的约瑟夫·B·兰伯特博士的研究。兰伯特教授将专注于将硅融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。通过利用其中一个反应来设计一种新的方法，将硅-氢键添加到碳-碳双键(氢硅化)，从而扩大了项目的范围，该过程是催化的，但避免了当前过程中必要的贵金属的使用。