CAS: Catalytic sp3 Carbon-Hydrogen (C-H) Functionalization with Earth Abundant Metals

通过这一奖项，美国国家科学基金会化学部的化学催化计划支持乔治敦大学化学系的蒂莫西·沃伦教授的研究，以开发连接大量化学构件的可持续催化剂。使用催化剂通过形成新的碳-碳、碳-氮和碳-氧键来连接分子片段通常需要多个步骤的化学过程来首先激活分子片段，使它们更具活性。沃伦教授和他的研究生和本科生研究团队正在设计新的方法，利用碳氢键连接化学构件。碳氢键很难打破，但在大多数原料化学品中都能找到。正在开发的用于这些反应的催化剂来自地球上丰富的铜。这些研究涉及旨在从根本上洞察催化剂如何工作以提高其在先进工业化学品制造中的性能的实验。该项目正在为不同的学生群体提供培训。沃伦博士和他的团队在华盛顿特区举行的一年两次的美国科学与工程节上向普通公众介绍化学。该团队将继续与处于科学生涯初期的年轻科学家合作。每年夏天，高中生将获得宝贵的经验，并有机会接触到一系列更有经验的科学家(本科生、研究生、PI)，同时为化工企业做出贡献。最后，沃伦教授和他的学生还将在每年夏天为来自Cristo Rey和KIPP网络的高三学生提供为期一天的动手实验体验，这些网络服务于贫困、低收入和不同的学生群体，说明化学与环境之间的联系。催化反应将丰富的化学原料中的碳-氢(C-H)键转化为增值的碳-氮(C-N)、碳-氧(C-O)和碳-碳(C-C)键，对于提高合成过程的效率很有价值。这些转变绕过了激活试剂所需的步骤，同时减少了废物。Warren教授和他的研究小组发现，铜催化的自由基接力反应可以用来使C-H键功能化，他们目前正在研究这种催化体系可以实现的新的合成转化。这些研究包括优化催化剂以适应与C-H键反应的新型试剂，探索新的氧化剂以减少目前所需的过量烷烃，以及研究C-H酰胺化的不对称体系。此外，正在进行基本机制研究，以收集有助于进一步发展和优化的信息。这些研究活动也是为不同的研究生、本科生和高中生提供培训的场所。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 this award, the Chemical Catalysis Program of the NSF Division of Chemistry is supporting the research of Professor Timothy Warren of the Department of Chemistry at Georgetown University to develop sustainable catalysts that link abundant chemical building blocks. Using catalysts to link molecular fragments by the formation of new carbon-carbon, carbon-nitrogen, and carbon-oxygen bonds usually requires multi-step chemical processes to first activate the molecular fragments so that they are more reactive. Professor Warren and his team of graduate and undergraduate researchers are designing new ways to connect chemical building blocks using carbon-hydrogen bonds that are difficult to break but found in most feedstock chemicals. The catalysts that are being developed for these reactions are derived from earth abundant copper. These studies involve experiments designed to gain fundamental insight into how the catalysts work to be able to improve their performance in the advanced manufacture of industrial chemicals. This project is providing training for a diverse group of students. Dr. Warren and his group introduce the general public to chemistry at the biannual USA Science and Engineering Festival in Washington, DC. The team will continue to work with young scientists at the beginning of their scientific careers. Each summer a high school student will gain valuable experience and access to a range of more experienced scientists (undergrads, grads, PI) while contributing to the chemical enterprise. Finally, Professor Warren and his students will also provide day-long, hands-on laboratory experiences each summer for rising high school seniors from the Cristo Rey and KIPP networks that serve underprivileged, low-income, and diverse student populations that illustrate connections between Chemistry and the Environment.Catalytic reactions for the conversion of carbon-hydrogen (C-H) bonds in abundant chemical feedstocks to value-added carbon-nitrogen (C-N), carbon-oxygen (C-O), and carbon-carbon (C-C) bonds are valuable for improving the efficiency of synthetic processes. These transformations bypass the steps required to activate reagents and simultaneously decrease waste. Professor Warren and his research group have discovered that a copper-catalyzed radical relay reaction can be used to functionalize C-H bonds and they are currently investigating new synthetic transformations that can be achieved with this catalytic system. These studies involve optimizing the catalyst to accommodate new types of reagents to react with the C-H bonds, exploring new oxidants to decrease the excess amount of alkane currently required, and investigating asymmetric systems for C-H amidation. In addition, fundamental mechanistic studies are being performed to collect information that will facilitate further development and optimization. These research activities also serve as a training ground for a diverse group of graduate, undergraduate, and high school students.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.