Collaborative Research: RUI: Manipulation of Arylene Ethynylene Structures and Properties via Coordination, Halogen Bonding and Hydrogen Bonding

美国国家科学基金会化学部的大分子、超分子和纳米化学计划支持该项目，以设计和合成新的碳基分子，用于柔性、高性能电子设备。对这些分子的研究可能会使我们更好地理解如何设计出理想的性能以及这些材料的功能。例如，控制共轭单体、低聚物和聚合物分子构象的能力不仅对操纵它们的电子性质很重要，而且对优化材料的整体电子性质也很重要。虽然材料内部的自由旋转会导致各种不可预测的，也许是不希望的分子包装排列，但加强平面性的策略可以提供增加的秩序和增强的电子性能。因此，受构象约束的芳炔乙烯是光伏、薄膜晶体管和发光器件发展的重要目标。同样，由于其刚性和可预测的几何形状，芳炔炔结构可以作为特定尺寸和形状的客人的主人。完全理解和优化这些系统的几何参数可能会导致新的传感能力。负责合成和表征这些新化合物的本科生在实验室获得实践经验，为他们在化学工业的职业生涯或研究生课程的额外学习做好准备。该项目在两个不同的校园进行，威斯康星大学史蒂文斯点分校和密苏里州立大学。这些大学的教授参与有意义的研究，不仅加强了对直接从事研究项目的学生的教育，而且也加强了对从课堂知识和技能转移中受益的学生的教育。该项目的科学目标是设计和制备具有分子水平控制电子特性、晶体设计和主客活性的新型芳炔-乙炔结构。具体来说，吡啶基在共轭体系中的结合为通过卤素键、氢键和过渡金属配位进行结构控制提供了机会。这些相互作用为产生新型液晶、增强不饱和骨架的有效共轭和高度特异性的主客体配对提供了途径。

The Macromolecular, Supramolecular and Nanochemistry Program of the NSF Division of Chemistry supports this project to design and synthesize new carbon-based molecules for potential use in flexible, high performance electronic devices. The study of these molecules may lead to a better understanding of how to design desirable properties as well as how these materials function. For example, the ability to control molecular conformations in conjugated monomers, oligomers, and polymers is not only important for manipulating their electronic properties, but also for optimization of the bulk electronic properties of a material. While free rotation within a material can lead to a variety of unpredictable, and perhaps undesirable, molecular packing arrangements, strategies for enforcing planarity can provide increased order and enhanced electronic properties. Arylene ethynylenes that are conformationally constrained are, therefore, important targets in the development of photovoltaic, thin-film transistor and light emitting devices. Similarly, with their rigidity and predictable geometries, arylene ethynylene structures can serve as hosts for guests of specific sizes and shapes. Complete understanding and optimization of the geometric parameters of these systems may lead to new sensing capabilities. Undergraduates responsible for synthesizing and characterizing these novel compounds gain hands-on experience in the laboratory, preparing them for careers in chemical industry or additional study in graduate programs. This project is conducted on two different campuses, University of Wisconsin-Stevens Point and Missouri State University. The participation of professors from these campuses in meaningful research enhances the education of not only the students working directly on the research projects, but also students who benefit from the transfer of knowledge and skills in the classroom.The scientific objective of this project is to design and prepare novel arylene ethynylene structures with features that allow molecular level control over electronic properties, crystal design, and host-guest activity. Specifically, incorporation of pyridinyl groups within conjugated systems offers an opportunity for structural control via halogen bonding, hydrogen bonding, and transition metal coordination. These interactions provide avenues for the generation of novel liquid crystals, the enhanced effective conjugation of unsaturated backbones, and highly specific host-guest pairing.