Mechanisms of Transition Metal Catalyzed Reactions in Hydrocarbons

化学结构、动力学和机理项目支持加州理工学院的Robert H. Grubbs教授开发一系列通过烯烃复分解反应进行烯烃相互转化的催化剂。美国国家科学基金会对这项工作的支持始于几十年前，当时已经确定了反应的基本机制。今天，这些催化剂发现自己广泛用于学术研究和重要的商业应用。这些进展包括发现新的无机配合物，这些配合物显示出更高的活性或选择性。一些限制仍然存在：目前的拨款侧重于新的催化剂系统，对区域化学和立体化学问题的更好理解，以及观察到的催化剂在乙烯存在下的低效率。这些配合物以一种新的机制起作用，随着机制的进一步了解，新的配体和配合物家族将被构建用于这些催化转化。钌配合物可诱导无环烯烃的复分解，也可用于环烯烃的开环聚合。使用这些配合物作为合成嵌段和高功能聚合物的活性引发剂，已经生产了许多定义明确的聚合物。有一类特殊的聚合物由于理论上的原因引起了人们的兴趣，并可能有有趣的应用，那就是无端聚合物——环状聚合物。制备了一组钌配合物，由环状单体生成环状聚合物。为了能够测试现有的理论，需要没有线性污染的纯循环聚合物。已经开发出一种方法，可以得到具有一定分子量范围的纯环。就更广泛的影响和社会效益而言，这些催化剂系统目前已被用于一系列成功的商业应用。需要使用这些催化剂闭合大环的新药正在开发中，并处于临床试验阶段。目前正在建设一个生物炼油厂，利用这些复合物将种子油转化为化学品和燃料。在新材料的生产中，需要NSF催化剂的聚合物已经在汽车市场上使用了很多年。此外，正在生产用于大型机械装置的新型高分子复合材料。

The Chemical Structure, Dynamics and Mechanism Program supports Professor Robert H. Grubbs of the California Institute of Technology for the development of a family of catalysts for the inter-conversion of olefins by the olefin metathesis reaction. NSF support for this work began decades ago with the determination of the basic mechanism of the reaction. Today these catalysts find themselves widely used in academic research and in significant commercial applications. These advances include the discovery of new inorganic complexes that show improved activity or selectivity. A number of limitations that remain: the present grant focuses on new catalyst systems, a better understanding of regiochemical and stereochemical issues and the observed low efficiency of the catalysts in the presence of ethylene. These complexes operate by a novel mechanism, and new families of ligands and complexes will be constructed for these catalytic transformations as the mechanism is better understood. The ruthenium complexes that induce the metathesis of acyclic olefins can also be used for the ring opening polymerization (ROMP) of cyclic olefins. Numerous well-defined polymers have been produced using these complexes as living initiators for the synthesis of block and highly functional polymers. A special class of polymers that is of interest for theoretical reasons and may have interesting applications are polymers without ends-cyclic polymers. A set of ruthenium complexes has been prepared that produce cyclic polymers from cyclic monomers. To be able to test standing theories, polymers that are pure cyclics without linear contaminations are required. A method has been developed that should result in pure cyclics with a range of molecular weights. In terms of broader impacts and benefits to society, these catalyst systems are currently being used for an array of successful commercial applications. New pharmaceuticals that require the closure of a large ring using these catalysts are being developed and are in clinical trials. A bio-refinery is being constructed that utilizes the complexes for the conversion of seed oils into chemicals and fuels. In the production of new materials, polymers that require the NSF catalysts in their production have been used in the automotive market for a number of years. In addition, new polymer composite materials are being produced for the construction of large-scale mechanical devices.