Synthetic and Mechanistic Studies of High Valent Organotransition Metal Compounds

在这项由无机化学、生物无机化学和金属有机化学计划支持的项目中，加州理工大学的约翰·E·伯考将研究新型与氧气兼容的过渡金属化合物的合成和性质，这些化合物可能能够选择性地氧化碳氢化合物。这项研究的最终目的是开发一种有用的催化方法，将碳氢化合物从煤、石油或天然气来源转化为醇(特别是甲烷转化为甲醇)，这种方法可能更易于运输和有用的能源或化学原料。该项目有两项工作：(1)合成新的可溶性Ru的氧代或过氧基衍生物，可以顺利地将烯烃转化为环氧化物或羰基化合物，将碳氢化合物转化为醇；(2)机理研究，涉及在Hf和Ta上形成碳-氧键或碳-氧键断裂。后一个项目将有助于理解影响过渡金属中心碳-氧和氢-氧键形成的动力学和热力学因素，这将有助于第(1)部分中催化剂的设计。本文还提出了相关研究，可提供一些与催化加氢脱硫化学相关的模型化合物和转化。

In this project supported by the Inorganic, Bioinorganic and Organometallic Chemistry Program, John E. Bercaw of the Calif- ornia Institute of Technology will investigate the synthesis and properties of new types of dioxygen-compatible transition metal compounds which may be capable of selectively oxidizing hydrocarbons. The eventual aim of this research is to develop a useful catalytic method for converting hydrocarbons from coal, petroleum or natural gas sources to alcohols (in particular, methane to methanol), which may be more readily transportable and useful energy sources or chemical feedstocks. The project has two thrusts: (1) synthesis of new soluble oxo or peroxo derivatives of ruthenium, which could smoothly convert olefins to epoxides or carbonyl compounds and hydro- carbons to alcohols, and (2) mechanistic studies which involve carbon-oxygen bond formation or carbon-oxygen bond cleavage at hafnium and tantalum. The latter project would lead to an understanding of the kinetic and thermodynamic factors influencing carbon-oxygen and hydrogen-oxygen bond formation at transition metal centers which would aid in design of the catalysts in part (1). Related studies are also proposed which could provide some model compounds and transformations of relevance to catalytic hydrodesulfurization chemistry.