Mechanisms of Transition Metal Catalyzed Reactions in Hydrocarbons

在化学学部有机动力学项目的支持下，加州理工学院的Robert Grubbs教授将继续研究一系列能够影响广泛应用的催化剂。这些催化剂表现出高水平的活性和选择性，这是通过对机理和结构功能关系的研究而得到的。在下一个授权期内，将开发和探索新的方法来合成配体，这将有助于从根本上理解控制这些系统效率的因素。这些研究将产生一种有效的方法来生成一系列n -杂环碳化合物，这些碳化合物可以用于除烯烃复分解以外的许多催化过程。虽然已经用钌、锇和铱制备了活性的分解催化剂，但迄今为止，还没有关于基于铁的中等效率的分解催化剂的报道。将制备和研究支持和稳定烷基铁的配体体系，以确定从钌催化剂中吸取的一些经验教训是否可以应用于铁基体系。拟议研究的另一个目标是探索合成新形式聚乙烯（PE）的路线，用于开发和测试结构-性能关系模型。发展完善线性和单分散聚乙烯的新路线，继续探索环状聚乙烯，开发合成超支化聚乙烯的新途径。已经建立了合作，以充分表征和比较每种拓扑不同材料的性质。此外，还提出了一种新的策略来开发两个烯烃之间的官能团交换（官能团复分解）催化剂，类似于烯烃的复分解，涉及两个烯烃之间的片段交换。这一策略将为烯烃的氧化、叠氮化和水化提供新的途径。特别的重点将放在一种催化剂的发展反马尔可夫尼科夫加水到烯烃。为了协助这些调查，将使用快速筛选技术，并进行基本的机制研究。加州理工学院的Grubbs教授提出的这一建议将生产出新的聚合物材料，供工业界和学术界的其他团体用于探索结构-性能关系。过去的项目产生了65篇以上的出版物和14项与烯烃复分解化学相关的专利。这些出版物要么是由NSF直接资助的，要么是由NSF资助开发的催化剂促成的。美国国家科学基金会资助项目的学术影响力可以通过每篇论文被引用90次排名前两名来证明。该研究项目已经培养了一批学生，他们现在是主要学术和工业机构的杰出研究人员。它吸引了来自世界各地的博士后和学生，并在十周的时间里支持2-4名本科生，让他们接触学术研究。格拉布教授的研究是许多工业流程的基础，并正在美国创造新的就业机会。

With the support of the Organic Dynamics Program in the Chemistry Division, Professor Robert Grubbs at The California Institute of Technology will continue to work on a family of catalysts that have been able to impact a broad range of applications. The catalysts have displayed high levels of both activity and selectivity, the understanding of which has resulted from studies of mechanisms and structure function relationships. During the next granting period, new methods will be developed and explored for the synthesis of ligands that will aid in the fundamental understanding of the factors that control the efficiency of these systems. Out of these studies will come an efficient method for generating an array of N-heterocyclic carbenes that can be used in many catalytic processes beyond olefin metathesis. Although active metathesis catalysts have been prepared from ruthenium, osmium and iridium, to date there are no reports of even a moderately efficient metathesis catalyst based on iron. Ligand systems that should support and stabilize iron alkylidenes will be prepared and investigated to determine if some of the lessons learned from ruthenium catalysts can be applied to iron-based systems. Another objective of the proposed research is to explore routes to the synthesis of new forms of polyethylene (PE) to be used to develop and test models of structure-property relationships. New routes will be developed to perfect linear and monodispersed PE, continue the exploration of cyclic PEs, and develop new approaches to the synthesis of hyper-branched PE. Collaborations have been established for the full characterization and comparison of the properties of each of these topologically diverse materials. Additionally, a new strategy to develop catalysts for the interchange of functional groups (functional group metathesis) between two olefins, similar to olefin metathesis, which involves the interchange of fragments between two olefins. This strategy will provide new routes for the oxidation, aziridination, and hydration of olefins. Special emphasis will be on the development of a catalyst for the anti Markovnikov addition of water to olefins. To aid in these investigations, rapid screening techniques will be used and fundamental mechanistic studies will be carried out.This proposal by Professor Grubbs at The California Institute of Technology will produce new polymeric materials that other groups both in industry and academia will use to explore structure-property relationships. The past program produced over 65 publications and 14 issued patents related to olefin metathesis chemistry. These publications were either directly funded by NSF or were made possible by catalysts developed using NSF funding. The academic impact of the NSF funded program is demonstrated by being ranked in the top two of most cited programs with 90 citations per paper. The research program has produced a number of students who are now outstanding researchers in major academic and industrial institutions. It brings postdoctoral fellows and students from around the world, and supports 2-4 undergraduates for a ten week period, exposing them to academic research. Professor Grubbs' research is the basis for a number of industrial processes and is creating new employment opportunities in the US.