Synthesis, Reactivity, and Photochemistry of Late Transition Metal Complexes Featuring Carbenium-based Ambiphilic Ligands

Texas A&M University, College Station TX

Investigators

Abstract

With the support of the Chemical Synthesis program of the Division of Chemistry, Professor François Gabbaï of the Department of Chemistry at Texas A&M University will investigate a new family of ligands containing a positively charged carbon unit positioned next to a metal-binding site. Ligands are molecular compounds designed to hold metal atoms and influence their ability to carry out and accelerate chemical reactions. These are essential to a broad range of chemical industries. Designing new ligands that can purposefully ameliorate the reactivity of metals is thus an important line of inquiry. The new ligands prepared in this research are designed to allow for a positively charged carbon unit to approach or combine with a metal atom, enhancing its reactivity. Next, the ligand-metal complexes are to be developed into platforms for the generation of solar fuels, thus impacting research on new energy storage strategies. In addition, the project will provide mentorship to diverse high school students and and present chemical knowledge to K-6 grade students in two-way dual language programs integrating native English and native Spanish. This project from the Gabbaï team at Texas A & M will investigate the synthesis and coordination chemistry of ambiphilic ligands featuring a carbenium ion positioned next to a phosphine- or carbene-based metal-binding site. Coordination of these ligands to late transition metals such as nickel, palladium, platinum, and gold affords a family of complexes in which the late transition metal is electronically impoverished via the formation of a charge transfer or electrostatic interaction between the metal and the carbenium unit. These atypical interactions will be characterized using structural, spectroscopic, and computational tools. The knowledge derived from these investigations is expected to provide a framework for the fine-tuning of metal-ligand interactions and provide organometallic chemists with new ways to influence the reactivity of late transition metal centers. If successful, these studies will lead to new opportunities in halogen photoreductive elimination chemistry and in carbophilic catalysis. 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.