Cummins Group

Researchers in the lab of Professor Christopher C. Cummins are engaged in a variety of synthetic chemistry research projects. Themes include the development of new practical methods for inorganic synthesis, the discovery of definitive examples of new reactions applicable to transformation of important small molecules such as N2, P4, CO2, CO, and H2, and synthesis from the elements. We are passionately engaged in the synthesis of new simple substances. For example, the AsP3 molecule has been obtained in pure form, and the chemistry of P2, AsP, and PN as ligands or as transient reactive intermediates is being elucidated. This is representative of our effort to unleash transition-metal chemistry for the manipulation of compounds composed of heavier main-group elements. New developments here offer an inroad to the synthesis of solid-state materials from molecular precursors. The Cummins group is grateful to the National Science Foundation for funding this research.
With the aim of contributing new chemistry to fuel the effort of renewable energy, we are pursuing a project in CO2 reduction and reversible sequestration. Reduction of CO2 to CO has the potential to remediate this greenhouse gas while providing a chemical fuel; we are investigating new chemical mechanisms for such a reduction atop a metal nitride platform, as an alternative to strategies that require binding of CO2 directly at a metal center.
Another project is in the area of uranium chemistry. Targeted here is the synthesis of complexes representing synthons for uranium in low formal oxidation states, in order to uncover new modes of small-molecule activation. This is connected to our interest in metal-ligand multiple bonding; to date we have made progress in the synthesis of U—N multiple bonds. Now we are targeting U—C multiple bonds also, for possible applications in catalysis.
Ligand design is crucial to any effort in metal-based reaction chemistry, synthesis, and catalysis. Our group has pioneered the use of sterically-demanding monodentate anilide ligands for engendering low coordination-number complexes of high reactivity. In addition, we have introduced bulky ketimide and enolate ligands also into our repertoire of new supporting ligands. Presently we are pursuing new ligand architectures including hexaanionic carboxamide cryptand structures for bimetallic cavities aimed at O—O bond chemistry. Also we are developing multidentate enolate and enamide structures for a wealth of potential applications.

The basic coordination chemistry of simple ligand types has attracted our attention. Along these lines we are exploring simple cyclic phosphates including P3O93- as ligands for cobalt in aqueous solution. This is a project inspired by the discovery of the Nocera oxygen evolving catalyst (Co-OEC) and is being carried out in collaboration with the Nocera group.