Cooperative Enamine-Hard Metal Lewis Acid Catalysis for New Asymmetric Organic Transformations

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With this award, the Chemical Catalysis Program is funding Dr. Hong Wang of the University of North Texas to develop new catalytic methods to synthesize chiral molecules. Chiral molecules exist as non-superimposable mirror images, the same difference as left and right hands. Many molecules, especially naturally-occurring organic compounds and many pharmaceuticals, are chiral and the two mirror image forms of the molecule often have different biological properties. Therefore, an important challenge in modern organic synthesis is to control the handedness of the product. The reactions being developed in this project are designed to provide concise and versatile synthetic pathways to construct 5- and 7-membered ring systems, with control of handedness, a difficult feat with currently available synthetic methods. Dr. Wang is actively engaged in joint efforts to attract a diverse group of students to science, technology, engineering, and mathematics (STEM) fields. Her outreach activities build upon her research and includes outreach summer research programs for undergraduate students from minority schools and high school students to establish interest in STEM fields at an early stage. Dr. Hong Wang and her research team are developing novel catalytic systems through merging enamine catalysis with hard metal Lewis acid catalysis. The feasibility of the reversed soft-hard strategy is investigated to solve the critical acid-base quenching problem involved in cooperative acid-base catalysis. Also, under investigation is which factors affect the formation of enamine from primary arylamines and ketones. [3+2] and [4+3] reactions are developed using cooperative enamine-hard metal Lewis acid catalysis to construct 5- and 7-membered ring systems. In addition, a new class of bimetallic complexes is explored to serve as chiral hard metal Lewis acid catalysts in asymmetric catalysis. The density functional theory (DFT) calculations are carried out to understand the structure-activity of these bimetallic catalysts and the mechanisms of the [3+2] and [4+3] reactions. To address the broader impacts of this project, Dr. Wang is actively engaged in initiating outreach programs to provide summer research opportunities to undergraduate and high school students with a focus on attracting female and minority students into STEM fields.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.