Cyclic and Polycyclic Polystannanes

在有机动力学项目的支持下，最近从卡内基梅隆大学搬到加州理工学院的Sita博士将研究环和多环聚锡烷的合成和化学。在每一种情况下，将通过描述控制所提出的一系列反应的空间和电子因素来进行合成，这些反应导致目标环和多环有机硅烷。一旦每个合成完成，新的有机硅烷将通过使用各种光谱方法来研究，以确认其分子结构，并研究在新的分子体系中与锡的键合性质。由此获得的数据将与现有的理论模型相关联。Sita博士的研究项目致力于提高对有机锡化合物的环和多环化学的理解水平，达到目前碳环体系所享有的水平。Sita博士对这些新系统的合成和化学的研究有望为以下方面提供新的见解：(1)空间应变的表达方式，并最终在环和多环有机锡化合物中进行结构调节；(2)新型有机锡基材料的发展；(3)有机锡化学合成策略的发展。Sita博士的研究可能会导致对控制结构/键合/物理性质关系和含有重元素（如锡）的系统中的化学反应性的各种因素的更好理解。他在这一领域的工作可能会引起有机和主要群体有机金属化学家以及结构化学家的兴趣。

With support from the Organic Dynamics Program, Dr. Sita, who recently moved from Carnegie Mellon University to California Institute of Technology, will study the synthesis and chemistry of cyclic and polycyclic polystannanes. Syntheses will be pursued in each case by delineating the steric and electronic factors which govern a proposed series of reactions that lead to the target cyclic and polycyclic organostannanes. Once each synthesis has been achieved, the new organostannane will be studied by using a variety of spectroscopic methods in order to confirm its molecular structure and to investigate the nature of bonding to tin in the new molecular system. The data thereby obtained will be correlated with existing theoretical models. %%% Dr. Sita's research program is concerned with elevating the level of understanding of the cyclic and polycyclic chemistry of organotin compounds to that which is presently enjoyed by carbocyclic systems. Dr. Sita's research on the synthesis and chemistry of these new systems is expected to provide new insight into: (i) the ways in which steric strain is expressed and, ultimately, accomodated structurally in cyclic and polycyclic organotin compounds, (ii) the development of new organotin-based materials, and (iii) the development of synthetic strategy in organotin chemistry. Dr. Sita's research is likely to lead to improved understanding of the various factors which govern structure/bonding/physical property relationships and chemical reactivity in systems that contain heavy elements (such as tin). His work in this area is likely to be of interest to organic and main group organometallic chemists as well as to structural chemists.