Unique Group Transfer and Coupling Reactivity Promoted by Middle and Late Transition Metals in Bulky Alkoxide Ligand Environments

碳二亚胺是一种经常用于化工和制药行业的分子。同样，酮亚胺是生产复杂医药化学品的分子起点，偶氮芳烃是纺织和食品工业中常用的染料。虽然所有这些都是有价值的工业试剂，但它们的一个严重缺点是它们都是从涉及汞和异氰酸酯等有毒试剂的浪费过程中获得的。为了减少这些问题，开发这些化合物的新路线是一个重要的目标。韦恩州立大学化学系的Stanislas Groysman博士和大谷州立大学化学系的Richard Lord博士得到化学部化学合成计划的支持，以开发制备偶氮芳烃、碳二亚胺和酮亚胺的新的、高效的方法。这项研究开发了新的具有成本效益的试剂，利用铁和钴等金属来高效地生产这些分子。实验室实验在格罗伊斯曼博士的实验室中进行，结果由洛德博士和他的学生进行的计算化学解释。韦恩州立大学是一所研究型研究生大学，而大谷州立大学主要是一所本科院校。这一合作为两所大学的学生提供了参与研究生和本科生研究体验的机会。金属结合的卡宾和硝烯的反应活性取决于金属络合物的电子结构，而金属络合物的电子结构受金属类型及其辅助配体环境的影响。现有的大多数中晚期的丁二烯/卡宾络合物使用强场辅助配体来稳定形式上的高价金属中心。该项目旨在开发具有弱场大体积双(醇)配位的中晚期过渡金属络合物。醇盐配体的电子性质和立体结构允许形成反应性的低配位物种。对从铬到镍的第一列过渡金属的化学作用进行了探讨。用计算化学方法探讨了醇盐配位场对电子结构的影响。合成工作在韦恩州立大学的格罗伊斯曼实验室进行，计算工作在格兰德州立大学的洛德实验室进行。研究型大学和以本科为主的机构之间的这种合作为两个机构的学生提供了宝贵的经验。该奖项反映了NSF的法定使命，并通过使用基金会的学术价值和更广泛的影响审查标准进行评估，被认为值得支持。

Carbodiimides are a type of molecule that are frequently used in chemical and pharmaceutical industries. Likewise ketenimines are molecular starting points for the production of complicated medicinal chemicals and azoarenes are commonly used dyes in the textile and food industries. While all of these are valuable industrial reagents, a serious disadvantage of all of them is that they are obtained from wasteful processes that involve toxic reagents such as mercury and isocyanate. In order to reduced these problems, the development of new routes to these compounds is an important goal. Dr. Stanislas Groysman, Chemistry Department, Wayne State University and Dr. Richard Lord, Chemistry Department, Grand Valley State University, are supported by the Chemical Synthesis Program of the Chemistry Division to develop new, efficient methods to prepare azoarenes, carbodiimides, and ketenimines. The research develops new cost-effective reagents that exploit metals like iron and cobalt to efficiently produce these molecules. The laboratory experiments are carried out in Dr. Groysman's laboratories and the results are interpreted using computational chemistry conducted by Dr. Lord and his students. Wayne State is a graduate research university, while Grand Valley State is a primarily undergraduate institution. The collaboration provides the opportunity for students from both institutions to be part of both graduate and undergraduate research experiences. The reactivity of metal-bound carbene and nitrene depends on the electronic structure of the metal complex, which is underwritten by the metal type and its ancillary ligand environment. Most existing middle and late nitrene/carbene complexes utilize strong-field ancillary ligands which stabilize formally high-valent metal centers. This project seeks to develop middle and late transition metal complexes featuring weak-field bulky bis(alkoxide) ligation. The electronic properties and the steric bulk of the alkoxide ligands allow the formation of reactive low-coordinate species. The chemistry is explored across the first-row transition metals from Cr to Ni. The effect of the alkoxide ligand field on the electronic structure is explored by computational chemistry. The synthetic work is carried out in the Groysman lab at Wayne State University and the computational work in the Lord lab at Grand Valley State University. This collaboration between a research university and a primarily undergraduate institution provides a valuable experience for students at both institutions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.