CRC: Probing the Dynamic Nanoscale Chirality of Folded Dendrimers for Selectivity

该奖项支持Jon Parquette、T.V. RajanBabu、Christopher Hadad（俄亥俄州立大学）和David Modarelli（阿克伦大学）为理解树状大分子的协同构象行为所做的合作努力。这组研究人员将把折叠树突状分子的内部结构和动力学信息与化学反应中的选择性联系起来。具体目标是：(1)探索在二级结构的特定位置包含催化位点（例如，活化基团，酸，碱或金属中心）的折叠树突状分子对反应的选择性；(2)开发计算方法来量化折叠树突状分子内动态构象相关性的性质和程度；(3)监测反应时间尺度上树突结构体积随反应坐标的变化情况。化学反应受参与反应的分子的形状和大小以及引起化学变化的催化剂的形状和大小的影响。这项研究将详细了解树状大分子的结构是如何变化的，以及这些变化可能对反应产生的影响。了解合成大分子的动态构象如何影响反应性和选择性，也可能有助于更好地理解生物大分子（酶、核酸）如何改变其构象并促进选择性化学反应。该项目由化学合作研究计划（CRC）资助，为本科生、研究生和博士后提供了获得有机合成、有机金属化学、大分子合成和表征、光谱学和计算技术等方面知识和技能的良好机会。

This award supports the collaborative efforts of Jon Parquette, T.V. RajanBabu, Christopher Hadad (at Ohio State University) and David Modarelli (at University of Akron) to understand cooperative conformational behavior of dendrimers. This team of researchers will correlate information about the internal structure and dynamics of a folded dendrimer with selectivity during a chemical reaction. The specific goals are (1) to explore the selectivity imparted to a reaction by folded dendrimers incorporating catalytic sites (e. g., activating groups, acid, base or metal centers) at specific locations within the secondary structure, (2) to develop computational methods to quantify the nature and extent of dynamic conformational correlation within folded dendritic molecules, and (3) to monitor volume changes in the dendron structure on the time-scale of the reaction as a function of the reaction coordinate.Chemical reactions are influenced by the shape and size of molecules that undergo the reactions and those of the catalysts that bring about the chemical change. This study will lead to a detailed understanding of how the structure of dendrimers changes, and what impact those changes might have on a reaction. Understanding how the dynamic conformations of synthetic macromolecules affect reactivity and selectivity may also lead to a better understanding of how biological macromolecules (enzymes, nucleic acids) change their conformation and promote selective chemical reactions. This project is funded through the Collaborative Research in Chemistry Program (CRC) and provides outstanding opportunities for undergraduate, graduate and postdoctoral students to acquire knowledge and skills in organic synthesis, organometallic chemistry, macromolecular synthesis and characterization, spectroscopy and computational techniques.