Single-Molecule and Single-Active-Site Studies of Chirality Transfer and Olefin Metathesis Reactions on Metal and Metal Carbide Surfaces

这项研究工作是基于对催化剂表面发生的化学反应的研究。只有当反应物分子在定制的催化剂表面相遇时，这些类型的催化过程才会迅速发生。汉字中的“催化剂”也可以用于“婚姻经纪人”。我们的研究旨在了解催化剂表面是如何引导和激活反应物的--一次一对--走向幸福的结合。引导力可以是残酷的，也可以是微妙的；催化剂可能需要在反应发生前将反应物分解成碎片，或者它可能只需要在分子的一个特定表面上诱导反应，就像在手性反应中一样。我们使用表面科学研究工具的组合来询问控制与催化剂表面接触的分子的反应性的力。这些技术能够分离表面上的单个活性部位，并能够观察这些部位周围单个分子的组织。我们与丹麦科学家合作解释数据。这些项目集中在两类反应上，手性或不对称催化和烯烃歧化。手性催化是药物和农用化学品合成的核心。烯烃复分解是制备分子材料的一种非常有效的绿色化学方法。从这些研究中收集到的分子细节对于除催化之外的许多其他领域的进展具有首要的重要性。这是因为固体表面被用作传感器和纳米设备等许多现代技术的字面基础。支配催化活性的化学力通常也支配着这类装置的功能质量。

This research effort is based on the study of chemical reactions that take place on catalyst surfaces. These types of catalytic processes only take place rapidly when the reactant molecules encounter each other on custom-made catalyst surfaces. The Chinese characters for 'catalyst' can also be use for 'marriage broker'. Our research is aimed at understanding how the catalyst surface guides and activates the reactants-one couple at a time-towards a happy union. The guiding forces can range from the brutal to the subtle; the catalyst may need to split the reactants into fragments before the reaction occurs or it may simply need to induce reaction on one specific face of a molecule, as in a chiral reaction. We use a combination of surface science research tools to interrogate the forces that govern the reactivity of molecules in contact with a catalyst surface. These techniques are able to isolate single active sites on the surface and are able observe the organization of individual molecules around these sites. We collaborate with Danish scientists in the interpretation of the data. The projects are centred on two families of reactions, chiral or asymmetric catalysis and olefin metathesis. Chiral catalysis is central to the synthesis of pharmaceutical and agrochemical products. Olefin metathesis is an extraordinarily effective Green Chemistry method for the preparation of molecular materials. The molecular details gleaned from these studies are of primary importance to progress in many other areas than catalysis. This is because solid surfaces are used as literally the foundation of many modern technologies such as sensors and nanodevices. The chemical forces governing catalytic activity often also govern the quality of function of such devices.