Transition Metal-Nitrogen Multiple Bonds

大卫威格利，化学系，亚利桑那大学，是由无机，生物无机和有机化学计划的过渡金属-氮多重键的化学研究的支持。有机亚氨基配体长期以来一直被用作辅助基团，以可变程度的空间保护和支持处于其最高氧化态的金属。然而，高度反应性的金属-酰亚胺部分不是众所周知的。本研究的总体目标是更好地理解过渡金属-氮多重键合，并开发利用金属-亚氨基部分的新方法。为了扩大其反应的范围，新的金属介导的烯烃氮杂环丙烷化反应将开发使用d2金属亚硝基和偶氮杂环丁烷与化学计量和催化过程，涉及亚胺中间体正在调查。在这些aziridinations可能的metallacyclic中间体将通过独立的路线制备，并作为机械探针检查。新的亚胺钌配合物将制备和它们的效用作为氮烯[NR]转移试剂将被探索。最后，金属-亚胺配合物将被开发为具有合成有机化学价值的电环重排试剂。高活性的金属-亚胺基团，其由过渡金属键合到带有单个额外取代基的氮组成，可以在一定条件下产生。这些金属-亚氨基络合物活化甲烷中的C-H键;在工业上重要的烯烃加氢胺化和烯烃氮丙啶化中发挥核心作用;并已用于模拟加氢脱氮、丙烯氨氧化和腈还原催化中的步骤。尽管反应性金属-亚氨基配合物的重要性，它们的数量仍然很少，它们的性质没有很好地系统化。本研究将合成一系列新的亚胺配合物，开发新的活化亚胺基的方法，拓宽其反应范围。

Dr. David Wigley, Chemistry Department, University of Arizona, is supported by the Inorganic, Bioinorganic, and Organometallic Chemistry Program for studies of the chemistry of transition metal-nitrogen multiple bonds. Organoimido ligands have long been used as ancillary groups to variable degrees of steric protection and to support metals in their highest oxidation states. However, highly reactive metal-imide moieties are not well known. The overall objective of this research is to gain a better understanding of transition metal-nitrogen multiple bonding and to develop new methods for utilizing metal-imido moieties. To extend the range of their reactions new metal-mediated alkene aziridination reactions will be developed using d2 metal-nitroso and -azo complexe with both stoichiometric and catalytic processes that involve imido intermediates being investigated. The probable metallacyclic intermediates in these aziridinations will be prepared by independent routes and examined as mechanistic probes. New imido complexes of ruthenium will be prepared and their utility as nitrene [NR] transfer reagents will be explored. Finally, metal-imido complexes will be developed as reagents for electrocyclic rearrangements of value to synthetic organic chemistry.Highly reactive metal-imide groups, which are composed of a transition metal bonded to a nitrogen that bears a single additional substituent, can be generated under certain conditions. These metal-imido complexes activate C-H bonds in methane; play a central role in the industrially important hydroamination of olefins and olefin aziridination; and have been used to model steps in hydrodenitrogenation, propylene ammoxidation, and nitrile reduction catalysis. Despite the importance of reactive metal-imido complexes, their numbers remain small and their properties are not well systematized. In this research a number of new imido complexes will be prepared, new methods for activating metal imido groups will be developed, and the range of their reactions will be extended.