Thermochemical and Reactivity Studies of Basic Transition Metal Complexes

碱性过渡金属配合物的热化学和反应性研究

• 批准号: 9103948
• 负责人: Robert Angelici
• 金额: $ 24万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-05-01 至 1994-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9103948&HistoricalAwards=false
• 关键词: Thermochemical; Reactivity; Studies; Basic; Transition

Many transition metal complexes behave as bases as illustrated by their reactions with protonic acids to give metal hydrides. There is evidence that this basicity also influences other types of reactivity of these complexes. To understand these reactivities, basicities of a variety of transition metal complexes will be determined by measuring their heats of protonation calorimetrically with triflic acid. Series of mononuclear complexes with a variety of ligands will be studied systematically in order to establish quantitative relationships between the metal basicity and the natures of the ligands attached to it. Electronic and steric effects of monodentate ligands will be examined, and basicity changes caused by distortions of reactant and/or product structures induced by chelating ligands will be studied. Also, factors which affect basicities of dinuclear and cluster complexes, where protonation occurs on a metal-metal bond, will be investigated. In order to understand how metal complex basicities influence other types of complex reactivity, rates of a variety of oxidative-addition reactions will be determined and correlated with the enthalpy values; such linear free energy correlations should be extremely useful guides to understanding a broad range of transition metal complex reactivity. %%% In this project in the Inorganic, Bioinorganic, and Organometallic Program of the Chemistry Division, Dr. Robert J. Angelici of Iowa State University will continue thermochemical and reactivity studies of a variety of transition metal complexes. It is possible that a limited set of thermochemical data may allow accurate predictions of a large range of chemical reactivities, a predictive capability that could prove very useful in the design of certain catalysts.

许多过渡金属配合物表现为碱，如图所示 通过它们与质子酸反应生成金属氧化物。 有证据表明，这种碱性也影响其他 这些复合物的反应性。 理解这些 各种过渡金属的反应性、碱度 复合物将通过测量它们的热来确定， 用三氟甲磺酸量热法进行质子化。 系列 单核配合物与各种配体将进行研究 为了建立定量关系， 金属的碱性和配体的性质之间 单齿的电子效应和空间效应 配体将被检查，和碱性变化引起的 反应物和/或产物结构的扭曲， 将研究螯合配体。 此外，影响 双核和簇合物的碱度，其中 质子化发生在金属-金属键上，将被研究。 为了了解金属络合物的碱度如何影响 其他类型的复杂反应性，各种 氧化加成反应将被确定和关联 与焓值;这种线性自由能相关性 应该是非常有用的指南，以了解广泛的 过渡金属络合物反应性的范围。 %%% 在这个项目中，无机，生物无机， 化学部有机物计划，罗伯特J。 爱荷华州州立大学的安杰利奇将继续热化学 和各种过渡金属的反应性研究 配合物 有可能是一组有限的热化学 数据可以允许对大范围的 化学反应，一种预测能力，可以证明 在某些催化剂的设计中非常有用。