RUI: Molecular Topology Directed Molecular Assembly Using Crystalline Quasiracemates

第1部分：非技术性总结固体材料的许多功能需要特定的分子选择性地相互作用。分子之间的这种特定的相互作用通常是由于控制组成构件的方向的强力和弱力的混合而产生的。虽然强相互作用已经得到了相当大的关注，但通过较少定义或弱接触产生较难管理的基序的化学特征对整个分子识别过程也很重要。分子形状就是这样的特征之一。这个项目由Kraig Wheeler教授指导，由惠特沃斯大学的一个本科生研究团队主持，通过使用分子形状的结构特征来创建排列成晶体的目标分子。这项研究得到材料研究部固态和材料化学项目的支持，其核心目标是开发不同种类的材料，利用形成预定组装的部件的形状空间。这项基础研究可能会通过开发构建块的分子特性为未来的功能固体设计打开大门。通过将研究与本科生在合成、晶体生长、结构确定和视频辅助显微镜方面的研究培训相结合，学生将成为STEM领域的科学家。第二部分：技术总结解开分子识别的细节继续引起广泛的科学学科的浓厚兴趣。分子组织成能量有利的固体的方式通常与互补的静电非键合接触和最佳匹配情况有关。这项研究在材料研究部固体和材料化学计划的支持下，专注于通过使用准外消旋方法构建双分子固体化合物来了解分子形状的结构边界对分子识别过程的影响。由已知的有机前体合成的手性构建块将通过氨基酸、羧胺和萘衍生物来合成。虽然准对映体材料的研究现在已经发展到一门成熟的科学，但组装准对映体对的密切细节仍然相对未知。这一建议探索了如何通过电荷辅助的非键接触和分子骨架尺寸的增加来增加晶格稳定性，从而有效地允许准对映体组分的更大的结构变化。晶格能量计算将结合结晶学、视频辅助热显微镜和量热研究来评估这些材料形成准外消旋组装的能力。该研究小组寻求在准外消旋体形成的背景下系统地理解“等结构”的定义，这可能被证明有助于探索负责分子识别的拓扑特征。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

PART 1: NON-TECHNICAL SUMMARYMany functions of solid materials require particular molecules to selectively interact with each other. This specific interaction between molecules often arises from a blend of both strong and weak forces that control the orientation of the component building blocks. While strong interactions have achieved considerable attention, chemical features that produce less manageable motifs via less well defined or weak contacts are also important to the overall molecular recognition process. Molecular shape is one such feature. This program, directed by Professor Kraig Wheeler and anchored by a research team of undergraduate students at Whitworth University, creates target molecules that align to form crystals by using the structural feature of molecular shape. A central aim of the research, supported by the Solid State and Materials Chemistry program within the Division of Materials Research, is to develop diverse families of materials that exploit the shape space of components that form predetermined assemblies. This basic research may open the door for the future design of functional solids via exploiting molecular properties of the building blocks. Through integration of the research with undergraduate research training in synthesis, crystal growth, structure determination, and video-assisted microscopy, students will be prepared as scientists for careers in STEM fields. PART 2: TECHNICAL SUMMARYUntangling the details of molecular recognition continues to hold intense interest to a wide range of science disciplines. The manner in which molecules organize into energetically favorable solids often relates to complementary electrostatic non-bonded contacts and best-fit scenarios. This research, supported by the Solid State and Materials Chemistry program within the Division of Materials Research, focuses on understanding structural boundaries of molecular shape to the molecular recognition process by using the quasiracemate approach for constructing bimolecular solid compounds. Chiral building blocks formulated from known organic precursors will be synthesized via amino acid, carboxylamide, and naphthyl derivatives. While the study of quasiracemic materials has now progressed to an established science, the intimate details of assembling pairs of quasienantiomers remains relatively unknown. This proposal explores how increasing crystal lattice stabilization via charge-assisted non-bonded contacts and an increased size of molecular framework effectively allows for greater structural variation of the quasienantiomeric components. Lattice energy calculations combined with crystallographic, video-assisted thermomicroscopy, and calorimetric studies will be used to assess the ability of these materials to form quasiracemic assemblies. The research group seeks a systematic understanding of the definition of "isostructural" in the context of quasiracemate formation that may prove useful for probing the topological features responsible for molecular recognition.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.