Unsaturated Hydrocarbon Cation Radical Chemistry

这项有机和大分子化学基金为威斯康星大学斯蒂芬·尼尔森教授的研究提供了支持，他的工作重点是有机自由基的化学。这些物种被认为是许多氧化过程中的重要中间体。充分了解氧化过程对控制各种氧化，特别是对有机分子具有破坏性的氧化具有重要的实际意义。通过光学和ESR光谱、PE光谱和循环伏安法研究不饱和烃衍生物电子去除后的核和电子结构变化。将测定气相和溶液中中性态和离子态之间的能量差。还将进行半经验计算。制备了一系列准双环烯烃，它们能改变电子损失时发生的锥体化的量。含C=C+化合物的比较。与除NN+外具有相同烷基的其它化合物作为形式荷电中心。承载电荷将揭示sigma， PI相互作用的差异。这些化合物的sigma， pi跃迁的辐照引发的化学也将被调查。在二氧与这些化合物（由它们的阳离子自由基引发）的链式反应中形成一氧化碳键的研究将继续进行。不同寻常的选择性是由过氧碳正离子和过氧阳离子自由基中间体，以及四元、五元和六元环过氧化物（二氧乙烷、二氧烯烃和内过氧化物）产生的，其中许多是其他方法无法得到的。这个阳离子自由基链催化（CRCC）化学扩展到一氧化碳，异腈，氧化亚氮和乙炔的添加将被探索。

This grant in Organic and Macromolecular Chemistry provides support for the research of Professor Stephen Nelsen, University of Wisconsin, whose work focuses on the chemistry of organic radical cations. Such species are thought to be important intermediates in a number of oxidation processes. A full understanding of oxidation processes has important practical implications in controlling a variety of oxidations, particularly ones that are destructive to organic molecules. Changes in nuclear and electronic structure upon electron removal from unsaturated hydrocarbon derivatives will be probed by optical and ESR spectroscopy, PE spectroscopy and cyclic voltammetry. Energy differences in the gas phase and in solution between the neutral and ionic state will be determined. Semiempirical calculations will also be carried out. A series of sesquibicyclic alkenes, which will change the amount of pyramidalization which occurs upon electron loss, will be prepared. Comparison of compounds with C=C+. as the formal charge-bearing center with other compounds having the same alkyl groups but NN+. bearing the charge will reveal differences in sigma, pi interactions. Chemistry initiated by irradiation into the sigma, pi transition of these compounds will also be surveyed. Studies of CO bond formation upon chain reaction of dioxygen with these compounds (initiated by their cation radicals) will continue. Unusual selectivities result from the peroxyl-carbocation and peroxide cation radical intermediates, and four, five, and six-membered ring peroxides (dioxetanes, dioxolanes, and endoperoxides), many of which are not available by other methods, have been shown to be formed. Extensions of this Cation Radical Chain Catalyzed (CRCC) chemistry to additions of carbon monoxide, isonitriles, nitrous oxide, and acetylenes will be explored.