CAREER: CAS: Organometallic Chemistry of Catalytically Relevant Copper(III) Complexes

In this CAREER project, funded by the Chemical Structure, Dynamics & Mechanisms B Program of the Chemistry Division, Wei Liu of the Department of Chemistry at University of Cincinnati is studying the fundamental reactivity of copper complexes for synthesizing important organic molecules. Compared to the precious metal analogues, copper catalysts are less expensive, less toxic, and have higher abundancy in the earth’s crust. However, the catalytic performance of copper complexes lags largely behind that of their precious metal counterparts, largely owing to limited understanding of the fundamental reactivity of copper complexes. The goal of this research is to study the reactivity of copper complexes that are plausible intermediates in catalytic Cu-mediated bond construction reactions. Investigations of the structure and reactivity of these complexes is directed at providing a deeper mechanistic understanding of known copper-catalyzed bond-forming reactions, enabling the development of improved copper catalysts, and inspiring the development of new copper-catalyzed transformations. Dr. Liu’s education plan focuses on increasing public awareness of the importance of organic chemistry in daily life and on the retention of underrepresented minorities in science through outreach programs at the Cincinnati Museum Center, research-based educational experiences, and online resources. High-valent organo-Cu(III) compounds have long been proposed as key intermediates in many Cu-catalyzed transformations. However, most reported examples of isolated Cu(III) species are stabilized by rigid macrocyclic chelating or perfluorinated ligands, and few of these examples provide experimental evidence for elemental reactions in Cu catalysis. In this project, the Liu research team will investigate the synthetic accessibility of reactive organo-Cu(III) compounds, study the elementary reactions of well-defined Cu(III) species, explore the structure of catalytically relevant Cu(III) complexes, and work to exploit their reactivity to discover new Cu-catalyzed transformations. An improved fundamental understanding of the reactivity of Cu(III) compounds, including homolytic dissociation, reductive elimination, and oxidative addition, would not only provide insights into existing reactions that involve Cu(III) intermediates but also inspire the development of novel Cu-catalyzed transformations. 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.