Studies of the halogen bond and electron transfer in prototypical donor-acceptor halogen-bonded complexes

在这个由化学系化学结构、动力学和机制项目支持的项目中，马奎特大学的斯科特·里德教授将研究涉及卤素原子的非共价相互作用，这在化学和生物化学的各个领域都非常重要，从蛋白质-配体相互作用和药物发现到分子识别和自组装，再到电子转移和有机合成。卤素键的强度可以与氢键相媲美或超过氢键，正如我们对氢键的不断发展的理解在很大程度上得到了模型系统研究的帮助一样，卤素键的研究需要对原型系统中的相互作用进行基本探测，这是本提案的重点。特别是，需要系统地将给体/受体的性质与卤素键的结构特征联系起来。Reid教授及其同事将在高水平从头算理论的帮助下，利用基质分离方法，结合远红外到紫外区的光谱探针，探测原型卤素键合系统的结构、性质、反应性和电子转移动力学。这项工作的一个关键方面是实验和计算方法的结合，这将对这一重要问题产生影响。在这些系统中，供体-受体配合物的电荷转移特征和电子转移动力学是支撑有机反应性的关键问题，本文所述的光化学研究将提供与卤素键光诱导电子转移相关的动力学的有价值的信息。通过对卤素键相互作用的关键类别（à-systems， O和S原子给体，N和P原子给体）的模型配合物的研究，将为卤素键的本质提供新的见解，这将有助于理论方法的发展和完善。项目成果将通过在高质量期刊上发表和参加诸如分子光谱学国际研讨会等国家和国际科学会议的方式传播，PI目前担任该会议的国际咨询委员会主席。PI还将利用这个项目扩大代表性不足的群体对研究的参与。

In this project supported by the Chemical Structure, Dynamics and Mechanisms Program of the Division of Chemistry, Professor Scott Reid of Marquette University will study non-covalent interactions involving halogen atoms, which are fundamentally important in diverse areas in chemistry and biochemistry from protein-ligand interactions and drug discovery to molecular recognition and self-assembly to electron transfer and organic synthesis. The strength of halogen bonds can rival or exceed that of hydrogen bonds, and just as our ever-evolving understanding of the hydrogen bond has been aided to a great degree by the study of model systems, the study of halogen bonding requires fundamental probes of interactions in prototypical systems, which is the focus of this proposal. In particular, the need exists to systematically correlate properties of the donor/acceptor with structural characteristics of halogen bonding. Prof. Reid and co-workers will probe the structure, properties, reactivity and electron transfer dynamics of prototypical halogen bonded systems, using matrix isolation methodologies in combination with spectroscopic probes from the far-IR to UV region, with assistance from high level ab initio theory. A key aspect of this work is the combination of experimental and computational methods that will be brought to bear on this important problem. The charge transfer character of donor-acceptor complexes and the dynamics of electron transfer in these systems are key issues that underpin much of organic reactivity, and the photochemical studies described herein will provide valuable information on the dynamics associated with photoinduced electron transfer across halogen bonds. Through the study of model complexes in the key classes of halogen bonded interactions (à-systems, O and S atom donors, N and P atom donors), fundamental new insights will be provided into the nature of halogen bonding, which will aid the development and refinement of theoretical methods. The project results will be disseminated by publication in high quality journals and participation at national and international scientific meetings such as the International Symposium on Molecular Spectroscopy, for which the PI currently serves as Chair of the International Advisory committee. The PI will also use this project to broaden the participation of underrepresented groups in research.