Oxidant-Controlled Decarboxylation Reactions

About This Grant

With the support of the Chemical Catalysis Program of the Division of Chemistry, Professor Hoover of the Department of Chemistry at the University of Minnesota-Twin Cities is studying new catalysts to convert carboxylic acids to value-added compounds. Current routes to synthesize molecules used in medicine, agriculture and materials applications rely on expensive starting materials and involve lengthy multi-step syntheses. In contrast, carboxylic acids are abundant starting materials that can be obtained from renewable sources. The development of new catalysts to utilize these precursors will improve the efficiency and sustainability of these processes by reducing the number of synthetic steps required and minimizing the formation of waste byproducts. The broader impacts of the project will extend to current and future high school teachers who will participate in summer research opportunities with the Hoover lab. This program will promote careers in science and engineering and aid in developing the STEM workforce by encouraging and enabling research participation by Minnesota’s current and future teachers. This project will establish two new classes of oxidant-controlled reactions of carboxylic acids. Although oxidative decarboxylation reactions are an attractive approach to generate a variety of value-added targets from simple and abundant precursors, there are limited examples of such reactions that operate with high efficiency and selectivity. The approach will leverage distinct oxidant-based conditions to achieve disparate but related decarboxylative transformations. First, copper-catalysts paired with nitroxyl radical oxidants will enable selective dehydrogenation while mitigating decarboxylation to access unsaturated carbonyl compounds. Second, a new metal-free oxidant-mediated decarboxylative amination will generate primary amines from heteroaromatic carboxylic acids. Mechanistic studies will provide a fundamental understanding of the influence of the oxidant on the decarboxylation steps and will lay the groundwork for establishing a library of reliable and predictive metal-catalyzed and metal-free decarboxylation reactions of (hetero)aromatic and aliphatic carboxylic acids. 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.