Problems in Bioinorganic and Metal Cluster Chemistry

无机化学、生物无机化学和金属有机化学项目属于过渡金属化学领域。该项目的一个目标是设计类似于酶反应的化学反应系统，从而证明某些酶的功能的可行反应途径，如含镍酶氢酶和一氧化碳脱氢酶。第二个目标是使用金属硫簇化合物来提供获得新型材料的途径。通过测定各种酶底物和Mo(VI)/Mo(IV)对之间的氧转移反应的动力学和机理，将进一步检验一大类钼酶作用机理的氧转移假说。这项工作将有助于发展氧转移反应性的热力学标度，也将发展基团转移反应性的定性标度。将开发模拟反应系统，以阐明镍酶氢酶和一氧化碳脱氢酶的作用。基于六钼八硫化物单体的多簇合物将通过Mo3S4簇合物的还原缩合或衍生簇合物的桥联，作为小分子和有序固体之间中间区域的化合物的例子来合成。团簇切割反应是指在固体中断裂团簇之间的桥键，并以衍生形式去除它们，将用于获得某些团簇，如Re6S8，到目前为止只能在高温下合成。

This project in the Inorganic, Bioinorganic and Organometallic Chemistry Program is in the area of transition metal chemistry. One aim of the project is to design chemical reaction systems which are analogues of enzymatic reactions, and thereby to demonstrate feasible reaction pathways for the function of certain enzymes, such as the nickel-containing enzymes hydrogenase and carbon monoxide dehydrogenase. A second aim is to use metal-sulfur cluster compounds to provide access to new types of materials. The oxotransfer hypothesis for the mechanism of action of a broad class of molybdoenzymes will be examined further by determination of the kinetics and mechanisms of oxo transfer reactions between a wide variety of enzyme substrates and Mo(VI)/Mo(IV) couples. This work will contribute to the development of a thermodynamic scale of oxo transfer reactivity, and a qualitative scale for group transfer reactivity will be developed as well. Analogue reaction systems will be developed for the elucidation of the action of the nickel enzymes hydrogenase and carbon monoxide dehydrogenase. Multiclusters based on hexamolybdenumoctachalcogenide monomers will be synthesized as examples of compounds in the intermediate domain between small molecules and ordered solids, using reductive condensation of Mo3S4 clusters or the bridging of derivatized clusters. Cluster excision reactions, which rupture bridge bonds between clusters in solids and remove them in derivatized forms, will be used to obtain certain clusters, such as Re6S8, which thus far have been synthesized only at high temperatures.