Hyperpolarization Catalysts for in situ Mechanistic Studies

在化学部化学合成计划的资助下，伊利诺伊大学厄巴纳-香槟分校化学系的艾莉森·富特将开发新的钴基化合物，这种化合物可以促进重要化学过程中的氢的反应。氢气是一种极其重要的化工原料，广泛应用于各种化工过程中。然而，就其本身而言，它不会做出反应或反应非常缓慢。为了绕过这个问题，人们开发了许多金属化合物，它们可以活化氢，大大加快其反应速度。这些化合物被称为催化剂，几乎都是以昂贵的稀有金属为基础的。该项目研究价格较低的金属钴的活化氢的能力。由于很难确定氢是如何添加到各种化合物中的细节，在这项研究中，将使用一种被称为仲氢的不寻常形式的氢，将测量的灵敏度提高到20万倍。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。福特教授和她的学生将参加3M暑期学者项目，该项目旨在为来自代表性不足群体的本科生提供研究经验，下一代伊利诺伊州科学家，吸引农村学校的小学生，以及女孩结合营，目标群体为6-8年级的女孩。该项目合成钴络合物，可用作对氢诱导极化(PhIP)催化剂。这要求抗磁性络合物在直接和间接超极化的整个催化循环中保持S=0。为了实现这一点并进入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的活性在包括烯烃、炔烃和芳烃在内的一系列底物上进行了评估，这些底物的官能团中具有长松弛核。一些底物是聚合催化中的关键反应物。在这些情况下，PhIP效应被用来检测和研究以前没有被遵守的机械中间体。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

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.