Patterns in Sigma Bond Complexation

西格玛键络合模式

• 批准号: 9401739
• 负责人: Robert Crabtree
• 金额: $ 39.65万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-05-15 至 1997-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9401739&HistoricalAwards=false
• 关键词: Patterns; Sigma; Bond; Complexation

9401739 Crabtree This project, supported by the Inorganic, Bioinorganic and Organometallic Chemistry Program, is concerned with the further development of the chemistry of X-H sigma-bonds (X=H, N, Si and its congeners, and M) coordinated to transition metals. This is a recently recognized area of organometallic chemistry for which the underlying principles are unclear; the goal of this reseach is to discover general trends across several classes of sigma-bond complexes. Among the several goals to be pursued are: generation of "stretched" dihydrogen complexes and new polyhydrogen species by steric crowding, demonstration of a change in reactivity for unsymmetrically bridged metal hydrides, and demonstration of a distinctive reactivity for sigma-bond bound N-H complexes. Techniques for detection and characterization of such compounds based upon NMR spectroscopy will be sought. %%% One of the most exciting recent developments in transition metal chemistry was the discovery that molecular hydrogen can bind to a metal complex without cleavage of the hydrogen-hydrogen bond. Professor Crabtree has played an important role in the elucidation of the factors that determine how molecular hydrogen will bind to a metal and in the development of spectroscopic techniques for determining the mode of binding. This project attempts to determine the role that such sigma-bond complexes play in transition metal chemistry of other X-H bonds. Ultimately the information obtained from this work will be important in the development of a better understanding of organometallic reaction mechanisms and may be useful in the design of more specific catalysts for industrially important reactions. ***

9401739 Crabtree该项目由无机，生物无机和有机化学计划支持，涉及与过渡金属配位的X-H σ键（X=H，N，Si及其同系物，和M）化学的进一步发展。 这是一个最近被认可的有机金属化学领域，其基本原理尚不清楚;本研究的目标是发现几类σ键复合物的一般趋势。 其中要追求的几个目标是：产生“拉伸”的二氢配合物和新的多氢物种的空间拥挤，演示的反应性的变化，不对称桥接的金属配合物，并演示一个独特的反应性σ键结合的N-H配合物。 将寻求基于NMR光谱法检测和表征此类化合物的技术。 过渡金属化学最近最令人兴奋的发展之一是发现分子氢可以与金属络合物结合而不断裂氢-氢键。 Crabtree教授在阐明决定分子氢如何与金属结合的因素以及发展用于确定结合模式的光谱技术方面发挥了重要作用。 本项目试图确定这种σ键配合物在其他X-H键的过渡金属化学中所起的作用。 最终，从这项工作中获得的信息将是重要的发展，更好地理解有机金属反应机理，并可能是有用的，在设计更具体的催化剂，工业上重要的反应。 ***