Hyperpolarization Catalysts for in situ Mechanistic Studies

用于原位机理研究的超极化催化剂

基本信息

批准号：
2324961
负责人：
Alison Fout
金额：
$ 47.5万
依托单位：
Texas A&M University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2023
资助国家：
美国
起止时间：
2023-04-01 至 2024-11-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2324961&HistoricalAwards=false
关键词：
Hyperpolarization Catalysts situ Mechanistic Studies

项目摘要

With funding from the Chemical Synthesis Program in the Chemistry Division, Alison Fout in the Department of Chemistry at the University of Illinois Urbana-Champaign, will develop new cobalt-based compounds that can facilitate the reactions of hydrogen in important chemical processes. Hydrogen is an extremely important chemical feedstock that is used a wide variety of chemical processes. However, by itself it does not react or reacts very slowly. To circumvent this problem a number of metal compounds have been developed that activate hydrogen and greatly speed its rate of reactions. These compounds are called catalysts and almost all are based on expensive, rare metals. This project studies the ability of a less expensive metal, cobalt, to activate hydrogen. As the details of how hydrogen adds to various compounds is difficult to determine, an unusual form of hydrogen known as parahydrogen will be used in this study to increase the sensitivity of measurements up to 200,000 times. In addition, the project aims to improve diversity, equity, and inclusion in the next generation of scientists. Prof. Fout and her students will participate in the 3M Summer Scholars Program, which aims to provide research experiences to undergraduate students from underrepresented groups, the Next Generation Illinois Scientist, which engages elementary students in rural schools, and the Bonding Camp for Girls, which targets 6-8th grade girls.This project synthesizes cobalt complexes that may serve as parahydrogen-induced polarization (PHIP) catalysts. This requires diamagnetic complexes that remain S=0 throughout the catalytic cycle for both direct and indirect hyperpolarization. To achieve this and to access a Co(I)/Co(III) catalytic cycle, complexes of ligands containing electron-rich moieties and carbenes are prepared. Their activity to catalyze PHIP is evaluated across a range of substrates including olefins, alkynes, and arenes, which feature long-relaxing nuclei in their functional groups. Some of the substrates are key reactants in polymerization catalysis. In these cases, the PHIP effect is used to detect and study of mechanistic intermediates that have not previously been observed.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在化学部化学合成项目的资助下，伊利诺伊大学厄巴纳-香槟分校化学系的 Alison Fout 将开发新的钴基化合物，这些化合物可以促进重要化学过程中氢的反应。氢气是一种极其重要的化学原料，广泛用于各种化学过程。然而，它本身不反应或反应非常缓慢。为了解决这个问题，人们开发了许多金属化合物来激活氢并大大加快其反应速率。这些化合物被称为催化剂，几乎全部都是基于昂贵的稀有金属。该项目研究了一种较便宜的金属钴激活氢的能力。由于氢如何添加到各种化合物的细节很难确定，因此本研究将使用一种不寻常的氢形式，即仲氢，将测量的灵敏度提高高达 200,000 倍。此外，该项目旨在提高下一代科学家的多样性、公平性和包容性。 Fout 教授和她的学生将参加 3M 暑期学者计划（该计划旨在为来自弱势群体的本科生提供研究经验）、下一代伊利诺伊州科学家计划（该计划吸引了农村学校的小学生）以及女孩联谊营（该计划旨在为来自农村学校的小学生提供研究经验）。针对 6-8 年级女生。该项目合成可用作仲氢诱导极化 (PHIP) 催化剂的钴络合物。这需要抗磁配合物在整个催化循环中保持 S=0 以实现直接和间接超极化。为了实现这一目标并进入 Co(I)/Co(III) 催化循环，制备了含有富电子部分和卡宾的配体络合物。它们催化 PHIP 的活性在一系列底物中进行了评估，包括烯烃、炔烃和芳烃，这些底物的官能团中具有长弛豫核。一些底物是聚合催化中的关键反应物。在这些情况下，PHIP 效应用于检测和研究以前未观察到的机械中间体。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。