Stabilization of Unique Chemical Bonding Environments and Exploration of Small Molecule Reactivity

作为我的团队正在进行的研究的一部分，在本提案中，我们将专注于以下跨越我们专业领域的项目，包括主族和过渡金属合成化学。基于增田研究小组的经验和优势，我建议继续研究并扩大我们在以下领域的知识： 1.半不稳定螯合配体：探索小分子反应性和催化作用的金属配合物 我们将扩展我们的配位化学研究我们的四芳基双金属配体和探索所得金属配合物的反应性。这种配体的半不稳定性是由强结合的阴离子取代基和较弱结合的芳基引起的。我建议继续这个项目与更令人兴奋的目标，包括利用潜在的氧化还原性质的半不稳定的teraryl基团，以帮助稳定低氧化态金属中心。这些物质然后可以用作较低氧化态金属的配体。这些将被测试与小分子和催化的进一步反应性。 空间体积大的双齿配体在主族金属、过渡金属和f区金属的配位化学中已被证明是非常重要的。通常，这些二齿配体由供体如亚胺、胺、膦亚胺、羰基、硫代羰基、醇盐和氧化膦组成。在不对称系统中，可以使用不同的供体来利用供体原子的硬度和柔软度的差异。叶立德在有机化学中是众所周知的，特别是作为维蒂希试剂，并且在配位化学领域中用作软的2-电子供体。在文献中很少有含有亚芴基的叶立德的例子。我们建议制备各种螯合配体，其中一侧具有典型的供体（N，O，S），另一侧具有灵活的碳基叶立德/亚芴基正膦片段。这种配体排列将允许分离通过硬亚胺和软叶立德片段配位的6元金属螯合物，或通过硬亚胺和芳族芴基阴离子的软的5元6电子部分配位的假6元螯合物。可能的是，在两种类型的螯合之间将存在流动性，并且可以利用这种流动性来影响金属络合物的反应性。 2.与具有N-杂环卡宾和氧膦基的小分子的反应性 十多年来，我一直在探索单重态卡宾和氧膦基自由基与各种小分子的反应性。这些包括具有反应性E-E键、E-H键的系统和扩展系统。我建议针对单重态卡宾和氧膦基自由基与一些外来的小分子/官能团的反应，以形成具有新的和意想不到的性质的新的官能团。

As part of the ongoing research within my group, in this proposal we will be focusing on the following projects that span our areas of specialty including main group and transition metal synthetic chemistry. Building upon the experience and strengths in the Masuda Research Group, I propose to continue research and expand upon our knowledge in the following areas: 1. Hemilabile chelating ligands: metal complexes for exploration of small molecule reactivity and catalysis We will extend our investigation of the coordination chemistry our teraryl cyclopentadienyl ligands and explore the reactivity of the resulting metal complexes. The hemilability of this ligands results from the strongly bound anionic cyclopentadienyl group and the more weakly -bound aryl group. I propose to continue with this project with more exciting targets including utilizing the potential redox properties of the hemilabile teraryl group to help stabilize low-oxidation state metal centers. These species can then be used as synthons for lower oxidation state metals. These will be tested for further reactivity with small molecules and in catalysis. Sterically bulky, bidentate ligands have proven to be very important in coordination chemistry of main group, transition, and f-block metals. Often, these bidentate ligands consist of donors such as imines, amines, phosphinimines, carbonyls, thiocarbonyls, alkoxides, and phosphine oxides. In the unsymmetrical systems, different donors may be used to exploit differences in the hardness and softness of the donor atoms. Ylides are well known in organic chemistry, particularly as Wittig reagents, and are used as soft, 2-electron donors in the area of coordination chemistry. There are few examples in the literature of ylides that contain the fluorenylidene group. We propose to prepare a variety of chelating ligands, where one side has an typical donor (N, O, S) and the other has the flexible, carbon-based ylide/fluorenylidene-phosphorane fragment. This ligand arrangement will either allow for the isolation of 6-membered metal chelates coordinated via the hard imine and the soft ylide fragment, or pseudo-6-membered chelates coordinated through the hard imine and the soft, 5-membered, 6- electron portion of the aromatic fluorenyl anion. It is possible that there will be fluxionality between the two types of chelation and this fluxionality can be exploited to affect the reactivity of metal complexes. 2. Reactivity with small molecules with N-Heterocyclic carbenes and phosphinyl radicals For well over a decade, I have explored the reactivity of singlet carbenes and phosphinyl radicals with a wide variety of small molecules. These include systems with reactive E-E bonds, E-H bonds, and extended -systems. I propose on targeting the reaction of singlet carbenes and phosphinyl radicals with a number of exotic small molecules/functional groups to form new functional groups with new and unexpected properties.