New High Oxidation State Inorganic Complexes of Later Transition Metals. Reaction Chemistry and Properties

无机、生物无机和有机金属化学项目的重点是过渡金属的高氧化态和不寻常氧化态的化学，如铜（III）、钴（IV）和钴(V)。该项目预计将导致发现有用和强大的新氧化剂，并提供某些金属酶的仿生模型，这些金属酶最近被发现含有高氧化态的金属，如半乳糖氧化酶，其中含有铜（III）方平面钴（III）配合物及其阴离子前体将被研究并用作高度氧化的有机金属物质的前体。这些配合物利用抗氧化的聚阴离子螯合（PAC）配体。由这些物种催化的氧原子转移将通过寻找末端钴(IV)-氧配合物来追求。最近发现的氧化醇的铜（III）配合物将作为半乳糖氧化酶和相关酶的仿生模型进行研究，并将用于铜（III）配合物在氧化过程中的作用的一般探索。将寻找在锇(VI)/(IV)体系催化的分子氧将磷化氢氧化为氧化磷化氢的中间体的证据。将研究PAC配体的钌配合物作为分子氧氧化烯烃的可能催化剂。将开发“热力学阶梯”来相互联系的形式还原势和异构平衡的非平面酰胺的非对映异构体的第一个热力学稳定，这些酰胺将与它们的平面类似物进行比较。研究高度保护的PAC配体的新配合物在液态二氧化硫中的电化学反应，以寻找与NHE相比形式还原电位大于2.5 V的溶液稳定的单电子氧化剂。还将尝试将电化学测量扩展到提供宽阳极范围的其他溶剂。

The focus of this project in the Inorganic, Bioinorganic and Organometallic Chemistry Program is the chemistry of high and unusual oxidation states of transition metals, such as copper(III), cobalt(IV) and cobalt(V). The project is expected to result in the discovery of useful and powerful new oxidizing agents, as well as providing biomimetic models of certain metalloenzymes which have recently been found to contain metals in high oxidation states, such as galactose oxidase, which contains copper(III). Square planar cobalt(III) complexes and their anionic precursors will be studied and employed as precursors to highly oxidized organometallic species. These complexes utilize oxidation-resistant polyanionic chelating (PAC) ligands. Oxygen atom transfers catalyzed by these species will be pursued especially by a search for terminal cobalt(IV)-oxo complexes. The recently discovered copper(III) complexes which oxidize alcohols will be studied as biomimetic models of galactose oxidase and related enzymes and will also be used in a general exploration of the role of copper(III) complexes in oxidation processes. Evidence will be sought for intermediates in the oxidation of phosphine to phosphine oxide by molecular oxygen catalyzed by osmium(VI)/(IV) systems. Ruthenium complexes of PAC ligands will be investigated as possible catalysts for alkene oxidations by molecular oxygen. "Thermodynamic ladders" will be developed to interrelate the formal reduction potentials and isomerization equilibria of diastereomeric complexes of the first thermodynamically stable nonplanar amides, and these amides will be compared to their planar analogues. The electrochemistry in liquid sulfur dioxide of new complexes of the highly protected PAC ligands will be explored in a search for solution stable one-electron oxidants with formal reduction potentials greater than 2.5 V vs. NHE. Attempts will be made also to extend the electrochemical measurements to other solvents offering a wide anodic range.