Mechanistic Chemistry of Transition Metal Oxygen and Oxo Complexes

爱荷华州立大学的James Espenson博士和Andreja Bakac博士得到了无机化学、生物无机化学和金属有机化学项目的支持，该项目研究在化学过程中单个氧原子(或同等碎片)从一个原子转移到另一个原子的过程机制。我们将研究几类这样的反应。其中之一是钼酸根等阴离子对高氯酸根离子还原的催化作用。将探索一氧化氮(NO)与超氧金属络合物和金属离子的反应性以及相关反应。这项研究还将扩展到类似氧的碎片(如硫)和与氧等电子的基团如NR和Cr2的转移。许多具有重大实际意义的化学反应涉及最初连接到一个分子的氧原子移动到另一个位置，在那里该原子连接到一个完全不同的分子。其他化学实体(硫原子、有机小碎片)参与化学变化，这些化学变化在重要方面与这些简单的原子转移过程非常相似。Espenson博士和Bakac博士将研究几个系统，这些系统有望极大地扩展对支配原子转移反应的基本原理的理解。这些系统中至少有两个也具有重大和直接的实际意义。在美国的许多地区，高氯酸盐离子污染是一种新的环境危害。原子转移还原是破坏高氯酸根离子的最好方法。一氧化氮(NO)是生物体内重要的信号转导因子。这个物种的功能很大程度上受到原子转移过程的影响。这项研究所寻求的基本理解将影响到这些和其他重要的过程。

Dr. James Espenson and Dr. Andreja Bakac of Iowa State University are supported by the Inorganic, Bioinorganic, and Organometallic Chemistry program for a program of research dealing with the mechanisms of processes in which a single oxygen atom (or equivalent fragment) is transferred from one atom to another during chemical processes. Several classes of such reactions will be studied. One of these is the catalysis of reductions of perchlorate ion by anions such as molybdate. The reactivity of nitric oxide (NO) with superoxo metal complexes and metal ions and related reactions will be explored. The research will also extend to the transfer of fragments that resemble oxygen (such as sulfur) and groups such as NR and CR2 that are isoelectronic with oxygen.Many chemical reactions that are of major practical significance involve movement of an oxygen atom originally attached to one molecule to another location, where that atom is attached to a quite different molecule. Other chemical entities (sulfur atoms, small organic fragments) participate in chemical changes that are quite similar, in important respects, to these simple atom-transfer processes. Drs. Espenson and Bakac will investigate several systems that hold promise of greatly extending understanding of the fundamental principles that govern atom-transfer reactions. At least two of these systems are also of major and immediate practical interest. Contamination by perchlorate ion is an emerging environmental hazard in many parts of the United States. Reduction by atom transfer is the best way to destroy perchlorate ion. Nitric oxide (NO) is known to be an important signaling agent within biological organisms. The functioning of this species is greatly influenced by atom transfer processes. Fundamental understanding sought in this research will bear on these and other important processes.