Gated Electron Transfer in Copper(II)/(I) Systems

有了这个奖项，无机，生物无机，和 有机化学计划提供支持， 大卫B博士参与的合作研究项目。 Rorabacher和罗纳德R.化学系的施罗德， 韦恩州立大学和Leo A.奥克里莫维奇 威斯康星大学欧克莱尔分校化学系。 他们 将合成一系列硫醚铜、硫胺素、 硫代吡啶络合物，其中铜（I）和铜（II） 氧化态是可接近的。 使用循环伏安法， 停流动力学、NMR谱线增宽研究，以及 选择的结构确定，他们将调查 配位体几何变化和转移之间的关系 电子往返于这些络合物中的铜中心。 在某些条件下， 在一个方向上的反应将被要求“门控”， 使中间体经历构象变化。 %%% 已知铜（I）和铜（II）的络合物具有 不同的几何形状，使得在氧化或还原时， 可能会发生构象变化。 一 构象变化产生了电子的能量势垒 转移 如果这个能量屏障可以被控制， 电子转移在一个 方向，也就是说，要“门”。“这个主题是 目前对生物化学的兴趣很大，因为 它在金属蛋白的反应中可能是重要的。 这 研究将有助于回答有关程度的问题， 蛋白质或其周围的构象变化 金属结合位点参与这种效应。

With this award, the Inorganic, Bioinorganic, and Organometallic Chemistry Program provides support for a collaborative research project involving Drs. David B. Rorabacher and Ronald R. Schroeder of the Chemistry Department, Wayne State University, and Dr. Leo A. Ochrymowycz of the Chemistry Department, University of Wisconsin-Eau Claire. They will synthesize a series of copper thiaether, thiaamine, and thiapyridine complexes in which both copper(I) and copper(II) oxidation states are accessible. Using cyclic voltammetry, stopped-flow kinetics, NMR line broadening studies, and selected structural determinations, they will investigate the relationship between ligand geometric changes and transfer of electrons to and from the copper centers in these complexes. It is expected that under some conditions the rate of the reaction in one direction will be "gated" by the requirement for the intermediate to undergo a conformational change. %%% Complexes of copper(I) and copper(II) are known to have different geometries, so that upon oxidation or reduction it is likely that conformational changes will occur. A conformational change creates an energy barrier to electron transfer. If this energy barrier can be controlled, then it becomes possible for electron transfer to occur in one direction, that is, to be "gated." This topic is of considerable current interest in biological chemistry, because it may be important in the reactions of metalloproteins. This research will help to answer questions about the extent to which conformational changes in the proteins or around the metal binding site are involved in this effect.