Access to “Inaccessible” Arynes and Redox Chemistry Using Transition Metals 

Assistant Professor Courtney Roberts - Department of Chemistry, University of Minnesota
Host - Brandi Cossairt

Research in the Roberts group involves looking at unsolved problems in organic synthesis through the perspective of organometallic/inorganic chemistry. One main area of interest for the group is the synthesis of heterocycles through aryne intermediates. Despite their useful reactivity, a number of challenges still remain in the use of arynes including problems with regioselectivity and the synthesis of N-heterocyclic arynes. Using fundamental principles of Ni chemistry, our group is the first to be able to access previously “inaccessible” 5-membered heterocyclic arynes for the first time since they were hypothesized to exist 120 years ago. We are also the first group to demonstrate catalyst controlled regioselectivity in arynes, where all previous examples operated under substrate control. Another challenge in organic synthesis lies in alkyl–alkyl cross-coupling. This is due to challenges with oxidative addition and off cycle pathways such as beta-hydride elimination. Our group has pioneered the use of Group 3 metal catalysts supported by redox-active ligands to overcome some of these challenges. Using 10 mol% of a Sc, Y, or Lu tris(amido) catalyst, coupling partners that both have beta-hydrogens can be successfully cross-coupled for the first time using early transition metals. These improvements related to organic synthesis can only be accessed using inorganic/organometallic chemistry. 
 
Prof. Courtney C. Roberts is an assistant professor and the 3M-Alumni Professor of Chemistry at the University of Minnesota. She obtained her B.S. in chemistry from Pepperdine University in Los Angeles, CA. She then pursued her graduate studies at the University of North Carolina at Chapel Hill, becoming the first graduate student in the laboratory of Prof. Simon Meek. During graduate school, Courtney developed rhodium olefin hydrofunctionalization catalysts using a new class of ligands called carbodicarbenes. After completing her Ph.D. in 2016, Courtney became a postdoctoral research fellow in the laboratory of Prof. Melanie Sanford at the University of Michigan where she explored C–H functionalization reactions using high valent Ni. Courtney began her career as an Assistant Professor at the University of Minnesota in the Fall of 2019. The Roberts group focuses on the development of d0 metal catalysts for alkyl–alkyl cross coupling as well as harnessing heterocyclic aryne intermediates for medicinally relevant building blocks. While at UMN, she has been the recipient of the Amgen Young Investigator Award, the ACS Leadership Development Award, the NSF CAREER Award, the NIH Maximizing Investigators Research Award, and the 3M-Alumni Professorship in Chemistry.