Synthesis and Reactivity of Metallaradicals

9421802特拉华州的Theopold大学克劳斯H. Theopold，化学系，特拉华州大学，是由化学系的无机，生物无机和有机化学计划的支持，研究顺磁性有机金属化合物的反应化学。该项目集中于铬，部分是针对理解和开发铬基催化剂。将制备一系列Cr（III）烷基化合物、更高氧化态的氧代铬烷基化合物和其中Cr氧化态大于（III）的亚烷基铬。这一阶段的调查的目标将是获得阳离子，催化活性的物种，这表明存在的agostic配体-铬相互作用，物种将作为氧化剂在有机反应。为了探索顺磁性铬离子之间的相互作用，将寻找一系列可能表现为分子磁体的铬氢化物团簇。将氧代配合物和簇合物的主题结合起来，制备一系列具有氧代立方烷或相关核的配合物。这些将模拟几种重要的商业烯烃聚合催化剂。 电子的行为就像小磁铁。在许多金属化合物中，有偶数个电子排列在一起，这样一个电子的磁性就被另一个电子的磁性抵消了。然而，有一些化合物具有奇数个电子，因此，这些化合物表现为小磁体。此外，奇数个电子通常会导致化学反应性增加。本项目的目标是制备一些不同类型的这些“顺磁性”复合物。这些物种将被评估为新试剂，重要工业过程的催化剂和磁性材料。

9421802 Theopold University of Delaware Dr. Klaus H. Theopold, Chemistry Department, University of Delaware, is supported by the Inorganic, Bioinorganic, and Organometallic Chemistry Program of the Chemistry Division to study the reaction chemistry of paramagnetic organometallic compounds. The project concentrates on chromium and is directed, in part, toward understanding and developing Cr based catalysts. A series of Cr(III) alkyls, higher oxidation state oxochromium alkyls, and chromium alkylidenes in which the Cr oxidation state is greater than (III) will be prepared. The goals of this phase of the investigation will be to obtain cationic, catalytically active species, ones which indicate the existence of agostic ligand-chromium interactions, and species which will serve as oxidants in organic reactions. In order to explore the interactions between paramagnetic Cr ions, a series of chromium-hydride clusters which may behave as molecular magnets will be sought. Uniting the oxo-complex and cluster themes, a series of complexes with an oxo-cubane or related core will be prepared. These will model several important commercial olefin polymerization catalysts. Electrons behave like little magnets. In many metal compounds there are an even numbers of electrons which align so that the magnetism of one is canceled by another. However, there are a few compounds which have an odd number of electrons and, consequently, these compounds behave as small magnets. In addition, an odd number of electrons often leads to increased chemical reactivity. The object of this project is to prepare a number of different types of these "paramagnetic" complexes. These species will then be evaluated as new reagents, as catalysts for important industrial processes, and as magnetic materials.