Chemical and Spectroscopic Studies of Radical Cation Reactivity and Structures

不寻常的自由基阳离子的结构和反应将被研究。通过适当的方法，包括光诱导电子转移、化学氧化和辐射分解，各种有机自由基阳离子将在一系列介质中产生，包括流体溶液、冷冻玻璃和固体载体，例如沸石。它们的结构和反应将通过各种现代光谱方法进行研究，包括稳态和时间分辨的光学和电子自旋共振光谱。此外，还将使用CIDNP和双光子(自由基阳离子光化学)来监测这些反应。中间体将被一系列试剂探测，这些试剂旨在拦截未配对的自旋(自由基加成)、电荷(亲核捕获)或这两种功能(超氧化物或半醌阴离子的环加成反应)。表面相互作用和外部约束对自由基阳离子及其重排的三维结构的影响将通过底物吸附在固体载体的微观表面或隔离在分子筛的三维包体中来探讨。%有机动力学项目的这笔拨款支持罗格斯大学海因茨·D·罗斯教授的工作。自由基阳离子是由中性分子失去一个电子而得到的，它是一种带有一个单位正电荷和一个未配对电子的活性中间体。稳定分子中的电子是配对的，而具有未配对电子的活性中间体被称为自由基。在这项研究中，将用现代仪器方法确定不寻常的自由基阳离子的结构，并研究这些中间体的反应。各种化学反应将被用来截取这些活性中间体，从而确定它们的结构。还将研究表面相互作用和外部约束对这些自由基阳离子反应的影响。

The structures and reactions of unusual radical cations will be investigated. A variety of organic radical cations will be generated in a range of media, including fluid solutions, frozen glasses, and solid supports, e.g., zeolites, by appropriate methods, including photo-induced electron transfer, chemical oxidation, and radiolysis. Their structures and reactions will be examined by a variety of modern spectroscopic methods, including steady-state and time-resolved optical and electron spin resonance spectroscopy. In addition, CIDNP and two-photon (radical cation photochemistry) will be used to monitor these reactions. The intermediates will be probed by a range of reagents designed to intercept the unpaired spin (free radical addition), the charge (nucleophilic capture), or both functions (cycloaddition of superoxide or semiquinone anion). The influence of surface interactions and external constraints on the three-dimensional structures of radical cations and their rearrangements will be probed by adsorbing the substrate on the microscopic surfaces of solid supports or sequestering in the three-dimensional enclaves of zeolites. %%% This grant from the Organic Dynamics Program supports the work of Professor Heinz D. Roth at Rutgers University. Radical cations are derived from neutral molecules by the loss of an electron to give a reactive intermediate with one unit of positive charge and one unpaired electron. Electrons in stable molecules are paired, while the reactive intermediates with unpaired electrons are referred to as free radicals. In this research, structures of unusual radical cations will be determined by modern instrumental methods and the reactions of these intermediates will be studied as well. Various chemical reactions will be used to intercept these reactive intermediates, and thereby determine their structures. The influence of surface interactions and external constraints on the reactions of these radical cations will also be investigated.