CAREER: Organic Transformations Enabled by Redox-Active Ligands and d0 Metals

在化学系化学催化项目的资助下，考特尼·罗伯茨博士和她的团队将致力于开发一种烷基-烷基交叉偶联反应，该反应使用3族和4族中丰富的和以前未利用的金属作为这种转化的催化剂。这些金属提供了理想的反应性，但由于它们的电子性质，以前没有用于这种反应。罗伯茨小组正在利用催化剂设计的力量来克服这一限制。通过克服这一挑战，将探索除交叉耦合之外的其他新型反应性。罗伯茨博士和她的团队将积极致力于促进研究生和本科教育的公平。这些活动包括一个名为cheMNext的项目，该项目致力于教育化学专业的少数族裔学生如何申请研究生院，以及为明尼苏达大学有机化学本科学生开发主动学习项目。开发新的催化方法来形成碳-碳键有可能影响社会的许多层面，从农业化学到材料化学。来自明尼苏达大学的Courtney Roberts博士和她的团队正在开发新的反应，这些反应需要使用早期过渡金属和氧化还原活性配体进行氧化还原。这种新的观点为解决与烷基-烷基交叉偶联相关的长期挑战提供了一种新的方法。罗伯茨小组发现，通过将早期过渡金属催化剂与氧化还原活性配体配对，它们能够促进这种交叉偶联，甚至与携带-氢的底物。由于这些早期过渡金属缺乏d电子，因此无法通过典型的氧化加成途径进行交叉耦合。它们倾向于存在于最高氧化态，也使得还原消除不利。通过使用三叉戟氧化还原活性配体，可以利用氧化还原化学来实现自由基催化。机制的见解将利用新的多组分反应开发基于自由基-极性交叉反应。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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 Catalysis program in the Division of Chemistry, Dr. Courtney Roberts and her group will work toward developing a an alkyl–alkyl cross-coupling reaction that uses earth abundant and previously unutilized metals in groups 3 and 4 as catalysts for this transformation. These metals provide ideal reactivity but have not been used before for this reaction due to their electronic nature. The Roberts group is leveraging the power of catalyst design to overcome this limitation. By overcoming this challenge, other new types of reactivity beyond cross-coupling will be explored. Dr. Roberts and her group will actively engage in efforts to promote equity in both graduate and undergraduate education. These activities include a program called cheMNext that engages in educating minoritized students in chemistry about applying to graduate school as well as the development of active learning programs for undergraduate organic chemistry at the University of Minnesota.Developing new catalytic methods to form carbon-carbon bonds has the potential to impact many levels of society from agricultural chemistry to materials chemistry. Dr. Courtney Roberts and her group from the University of Minnesota are developing new reactions that require redox events using early transition metals and redox active ligands. This fresh perspective offers a new approach to address the long-standing challenges associated with alkyl–alkyl cross-coupling. The Roberts group has found that by pairing early transition metals catalysts with redox active ligands they are able to facilitate such cross-couplings even with substrates that bear beta-hydrogens. These early transition metals have not been utilized for cross-coupling previously due to their lack of d electrons and hence the inaccessibility of typical oxidative addition pathways. Their propensity to exist in the highest oxidation state, also makes reductive elimination unfavorable. By using tridentate redox-active ligands, redox chemistry can be leveraged to enable radical catalysis. Mechanistic insights will be leveraged for new multicomponent reaction development based on radical-polar crossover reactivity.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.