Anion-pi and halogen-bonded complexes in thermal and photochemical reactions

波尔州立大学的Sergiy Rosokha教授得到了化学系大分子、超分子和纳米化学项目的支持，研究分子之间的弱相互作用力及其在需要热或光能形成产物的化学反应中的作用。所研究的特定非键相互作用（阴离子pi和卤素键）使分子聚集在复杂的超分子结构中。该项目有助于确定有效地将非键相互作用纳入分子设计的要求，为从带电和卤化分子中合成独特化学物质的更有效和更环保的合成程序提供新的工具，这些化学物质在生物系统和环境中无处不在。该项目预计将影响许多领域，如药物开发、环境修复和材料开发。该项目的跨学科性质为主要本科院校的不同本科生群体提供了各种现代实验化学研究技术以及计算化学的培训。该项目建立在Rosokha教授最近的发现的基础上，除了控制超分子复合物的结构外，阴离子-和卤素键促进相互作用物种之间的电子运动，这可以启动各种化学转化。该项目的具体目标是在进行热或光诱导反应（例如，卤素和/或电子转移，亲核取代等）的系统中识别和表征卤素键合和阴离子π配合物，并确定这些配合物在这些反应中的机制作用。为了实现这些目标，研究了阴离子或卤素键合配合物的形成以及键合物质之间的化学或光化学反应。这种体系中的瞬态配合物是通过低温和停流紫外-可见测量和x射线结构分析分离和表征的。结合热、光诱导反应的动力学测量以及计算分析，可以确定中间配合物的性质及其在反应机制中的作用。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Professor Sergiy Rosokha of Ball State University is supported by the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry to study weak interaction forces between molecules and their role in chemical reactions that need heat or light energy to form products. The specific non-bonding interactions under study (anion-pi and halogen bonding) enable the aggregation of molecules in elaborate supramolecular structures. The project helps define the requirements to efficiently incorporate the non-bonding interactions into molecular design, producing a new tool for more efficient and environmentally benign synthetic procedures for unique chemicals from charged and halogenated molecules, which are ubiquitous in biological systems and the environment. The project is expected to impact many fields, such as drug development, environmental remediation and materials development. The interdisciplinary nature of the project provides a diverse group of undergraduate students in a primarily undergraduate institution with training in a variety of modern experimental chemistry research techniques, as well as computational chemistry. The project builds on the recent findings by Professor Rosokha that, in addition to controlling the structures of supramolecular complexes, anion- and halogen bonding facilitate electron movement between interacting species, which can initiate a variety of chemical transformations. The specific objectives of the project are to identify and characterize halogen bonding and anion-pi complexes in the systems undergoing thermal or light-induced reactions (e.g., halogen and/or electron transfer, nucleophilic substitution, etc.) and to determine the mechanistic role of these complexes in such reactions. To achieve these objectives, the systems in which formation of anion-pi or halogen-bonded complexes is followed by the chemical or photochemical reactions between bonded species, are studied. Transient complexes in such systems are isolated and characterized using low-temperature and stopped-flow UV-Vis measurements and X-ray structural analysis. Together with the measurements of the kinetics of thermal and light-induced reactions, as well as computational analysis, this allows to establish the nature of the intermediate complexes and their role in the reaction mechanisms.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.