New Hydrocarbon-Stabilized Metal-Atom Reagents

无机化学、生物无机化学和金属有机化学项目的研究奖支持明尼苏达大学双子城分校的约翰·E·埃利斯教授在低价过渡金属化学领域的研究。目标包括定义“超还原”过渡金属化学的极限，并对配位配体的还原提供新的理解。在这些碳氢化合物的存在下，通过还原金属卤化物或相关的前驱体，将通过还原金属卤化物或相关的前驱体，在这些碳氢化合物的存在下，通过还原金属卤化物或相关的前体，制备出具有前所未有的形式氧化态的过渡金属，如Sc(I-)、V(II-)和Cu(I-)，或非常罕见的，如Hf(0，II-)、Ta(I，0)和Ni(I-，II-)的过渡金属络合物。只要有可能，新化合物将被分离出来并进行充分的表征。阴离子聚芳烃稳定的络合物有望成为“裸露”原子金属阴离子M(Z-)的独特可储存来源。它们与氮、一氧化碳、异氰化物、膦和其他受体配体的反应将被探索为合成迄今未知类别的低价金属络合物的途径。开发新的碳氢化合物稳定的金属原子试剂的传统路线将使其他研究人员能够接触到这种高活性物种，他们无法获得最初制备相关物种所需的专门且昂贵的金属蒸气反应堆设备。该项目对新一代科学家和教育工作者的教育、培训和专业发展也很重要，其中包括本科生和研究生、访问教员和其他博士后助理，特别鼓励少数民族和妇女参与。聚芳烃金属络合物可能是固氮试剂、不饱和有机和无机聚合物的催化剂以及新型多金属化合物的前驱体。该项目致力于开发通向新的不稳定碳氢化合物络合物的简便和可重复的路线，并使用这些物种作为试剂，对以前未知或罕见的形式氧化态的过渡金属的化学进行一般研究。通过这种方式，我们有望为我们对过渡金属化学的基本理解做出重大贡献。

The Research award in the Inorganic, Bioinorganic and Organometallic Chemistry Program supports the work of Professor John E. Ellis at the University of Minnesota-Twin Cities for research into previously unexplored areas of low valent transition metal chemistry. Objectives include defining the limits of "superreduced" transition metal chemistry and providing new understanding of the reduction of coordinated ligands. Naphthalene, anthracene, and other polycyclic aromatic hydrocarbon,or polyarene, complexes containing transition metals in formal oxidation states that are unprecedented, such as Sc(I-), V(II-), and Cu(I-), or very rare, such as Hf(0, II-), Ta(I, 0), and Ni(I-, II-), will be prepared by reduction of metal halides or related precursors in the presence of these hydrocarbons. The new compounds will be isolated and fully characterized whenever possible. Anionic polyarene-stabilized complexes promise to be of particular interest as unique storable sources of "naked" atomic metal anions, M(Z-). Their reactions with dinitrogen, carbon monoxide, isocyanides, phosphanes, and other acceptor ligands will be explored as a route to hitherto unknown classes of low valent metal complexes. The development of conventional routes to new hydrocarbon-stabilized metal-atom reagents will enable access of such highly-reactive species by other investigators, who do not have access to the specialized and expensive metal-vapor reactor apparatus originally required for the preparation of related species. This project is also important in the education, training, and professional development of a new generation of scientists and educators, including undergraduate and graduate students, visiting faculty, and other post-doctoral associates, where participation by minorities and women is particularly encouraged. Polyarene metal complexes are possible reagents for nitrogen fixation, catalysts for new polymers of unsaturated organic and inorganic species and precursors to novel polymetallics. This project endeavors to develop facile and reproducible routes to new labile hydrocarbon complexes and employ these species as reagents for a general investigation of the chemistry of transition metals in previously unknown or rare formal oxidation states. In this fashion significant contributions to our fundamental understanding of transition metal chemistry are anticipated.