RUI: Platinum-Catalyzed Selective Carbon-Hydrogen (C-H) Functionalization Reactions: Mechanism and Synthetic Utility

East Carolina University, Greenville NC

Investigators

Abstract

The Chemical Catalysis Program of the NSF Division of Chemistry is supporting the research of Professors Shouquan Huo and Yumin Li at East Carolina University developing catalytic reactions that convert a carbon-hydrogen bond into a carbon-carbon bond. By exchanging these bonds, subsequent reactions can produce more complex molecules that can be used as building blocks in drug discovery and materials science. Drs. Huo and Li are working with undergraduate and master's-level students to gain a deeper understanding of the reaction mechanisms by using both laboratory experiments and theoretical calculations. Dr. Huo expands his innovative 1-2-3 Undergraduate Research Enhancement Program to attract more students to research and to train them more effectively. This project is broadening the participation of students from underrepresented groups and engaging high school students through collaboration with the East Carolina University Summer Ventures in Science and Mathematics (SVSM) Program. The project is also preparing students for a stronger national scientific workforce and contributing to educational, economic, and societal development in the eastern Carolina region. Drs. Huo and Li are studying a unique platinum-catalyzed carbon-hydrogen (C-H) acylation reaction and advancing this underdeveloped reaction into a practical synthetic method. Compared to other metal-catalyzed C-H acylation reactions, this platinum-catalyzed reaction is free of oxidants and other additives, and also free of undesired decarbonylative side reactions. As such, efficient methods to introduce alhpa-, beta-, and gamma-keto ester functional groups, diketone groups, and various other acyl groups into a variety of aryl-heteroaryl ethers, are being studied, thereby creating many biologically and/or medicinally interesting building blocks. Drs. Huo and Li are also investigating the mechanism of this platinum-catalyzed reaction using a combined experimental and computational approach. Experimental studies are unveiling the underlying factors controlling the reactivity and selectivity of the reaction while density functional theory (DFT) and the nudged elastic band (NEB) methods are being used to locate the lowest energy pathway of the reaction and predict the structures and stabilities of key intermediates and transition states. DFT is also being employed in the design of new catalysts. This research is advancing fundamental knowledge in organometallic chemistry while providing efficient methods to a broad organic chemistry community. Further, undergraduate students, master's-level graduate students, and high school students are engaged in the synthesis and characterization of organic and organometallic compounds, computational modeling, data analysis, and dissemination of research results. 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.