Reactive Intermediates, Reaction Mechanisms, and Catalytic Cycles in the Gas Phase

反应中间体、反应机理和气相催化循环

• 批准号: 1565852
• 负责人: Mohamed Samy El-Shall
• 金额: $ 38万
• 依托单位: Virginia Commonwealth University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-05-01 至 2021-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1565852&HistoricalAwards=false
• 关键词: Reactive; Intermediates; Reaction; Mechanisms; Catalytic

The Chemical Structure, Dynamics and Mechanism Program of the NSF Chemistry Division supports the research of Professor Scott Gronert in the Department of Chemistry at Virginia Commonwealth University. Professor Gronert and his students are developing and using novel gas-phase techniques to study catalytic reactions that are important in the synthesis and production of pharmaceuticals and other fine chemicals. Their methodologies involve converting mass spectrometers into gas-phase reactors, and allow them to probe individual steps in complex reaction processes, with the goal of finding ways to improve the efficiency and selectivity of current catalysts. Professor Gronert and his group are also using this technology to seek out new catalytic systems that have superior properties to those currently in use. Professor Gronert's research program is deeply engaged in training students at all levels and encourages undergraduates to participate in independent research projects early in their college careers. In addition, Professor Gronert recruits one student each summer from a local HBCU (historically black college or university) to participate in a research project. The exceptional versatility of modern mass spectrometry offers unique opportunities for studying reactive intermediates under highly-controlled conditions and probing their intrinsic reactivity. The Gronert group has converted ion-trap mass spectrometers into ion reactors and uses them to study gas-phase reaction kinetics and equilibria. A central focus of the research involves isolating and characterizing key reactive intermediates in important catalytic cycles. In this project, three systems involving ligated metal complexes are being investigated: (1) The scope of new phenanthroline-based iridium(III) C-H activation catalysts; (2) New, 2-electron reduction methodologies to generate potential intermediates in cobalt- and nickel-catalyzed C-C coupling reactions; and (3) New 1-electron reduction methodologies to generate transition metals in unusual oxidation states and characterize their roles in reaction processes. In addition, a variable temperature ion reactor are being used to examine enthalpy/entropy effects in templated, gas-phase reaction systems. The outreach plan is tightly integrated into the research and a key component involves recruiting students each year from a local historically black university, Virginia Union University.

NSF 化学部的化学结构、动力学和机理项目支持弗吉尼亚联邦大学化学系 Scott Gronert 教授的研究。 Gronert 教授和他的学生正在开发和使用新型气相技术来研究对于药物和其他精细化学品的合成和生产非常重要的催化反应。 他们的方法涉及将质谱仪转换成气相反应器，并允许他们探测复杂反应过程中的各个步骤，目的是找到提高现有催化剂效率和选择性的方法。 格罗纳特教授和他的团队还利用这项技术来寻找新的催化系统，这些系统具有比目前使用的系统更优越的性能。 格罗纳特教授的研究项目深入致力于培养各个级别的学生，并鼓励本科生在大学生涯早期参与独立研究项目。 此外，格罗纳特教授每年夏天都会从当地的 HBCU（历史悠久的黑人学院或大学）招收一名学生来参加一项研究项目。现代质谱的卓越多功能性为在高度控制的条件下研究反应中间体并探测其内在反应性提供了独特的机会。 Gronert 小组将离子阱质谱仪改造为离子反应器，并用它们来研究气相反应动力学和平衡。 该研究的一个中心焦点涉及分离和表征重要催化循环中的关键反应中间体。 在该项目中，正在研究涉及配位金属配合物的三个系统：（1）新型菲咯啉基铱（III）C-H活化催化剂的范围； (2) 新的 2 电子还原方法，用于在钴和镍催化的 C-C 偶联反应中生成潜在的中间体； (3) 新的 1 电子还原方法，用于生成异常氧化态的过渡金属并表征它们在反应过程中的作用。 此外，变温离子反应器还用于检查模板化气相反应系统中的焓/熵效应。 推广计划与研究紧密结合，其中一个关键部分是每年从当地一所历史悠久的黑人大学弗吉尼亚联合大学招募学生。