Research activities in the Bebout research group are directed towards understanding differences in the biological activity of physiologically essential zinc and its toxic Group 12 counterparts cadmium and mercury. We use multidentate chelating ligands to moderate opportunities for intramolecular reorganization and intermolecular exchange, thereby overcoming some of the challenges associated with the broad coordination number and geometry tolerances of d10 metal ions. New complexes are characterized by a combination of X-ray crystallography, NMR spectroscopy and electrospray ionization mass spectrometry using departmental instrumentation. Collaborations with over 100 BS, ten MS degree candidates, one postdoc and a handful of other talented collaborators have produced over 30 peer-reviewed publications documenting the versatility of this multifaceted approach.
Recent Publications
Aggregation behavior of all three stable group 12 metal ions with a mixed NS(thiolato) donor ligand compared for the first time
“Solid State Structures and Solution State Behavior of Group 12 Complexes of a Tripodal Mixed NS(thiolato) Donor Ligand” New J. Chem. 2024, 48, 2547 – 2557. DOI: 10.1039/D3NJ05532A.
Highlights:
Group 12 complexes incorporating mixed aromatic amine-alkylthiolated ligands have rarely been investigated despite the common prevalence of histidine and cysteine in coordination environment of these metal ions when bound to proteins; metal ion dependent differences in solution state and solid state aggregation are reported.
Other coauthors include Michelle A. Sturner (BS Chemistry W&M 2018 & MS Chemistry W&M 2023), Isla D. Thomas (pursuing a W&M BS in Physics), Joshua E. Owusu-Koramoah (BS Chemistry W&M 2020), Todd M. Reynolds (BS Chemistry W&M 2023, pursuing a W&M MS in Chemistry), Steven M. Berry (Camille & Henry Dreyfus Postdoctoral Fellow at W&M 2003-2005; currently Associate Professor and Chemistry Department Chair University of Minnesota Duluth), Raymond J. Butcher (crystallography collaborator from the Chemistry Department at Howard University).
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Dramatic shift in crystallized Hg-ligand aggregate with counterion change
“Crystal structure and Hirshfeld surface analysis of cyclo-tetrabromido-1κ2Br,3 κ2Br-tetrakis(μ2-2-{[(pyridin-2-yl)methyl]amino}ethane-1-thiolato κ3N,S:S)tetramercury(II)” Acta. Cryst. 2023, E79, 952-957. DOI: 10.1107/S205698902300823X.
Highlights:
- Macrometallacyclic complex characterized by X-ray crystallography
- Alternating Br2S2 and distorted N2S2 primary Hg coordination environments
- Backfolded chair ring conformation suggesting interactions between non-bonded Hg and Br atoms
- Supramolecular interactions include four-fold aryl embrace and H-bonds with Br as the acceptor
- Hirshfeld surface analysis completed
- Structurally unlike bicyclic complex of Hg(ClO4)2 previously characterized with same ligand (DOI: 10.1039/C000002G)
Other coauthors include Isla D. Thomas (pursuing a W&M BS in Physics), Kathryn R. (Stephenson) Kocher (BS Chemistry W&M 2011), Julie A. Viehweg (BS Chemistry W&M 2002) colleague Robert D. Pike.
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“Homo- and Heteronuclear Group 12 Metallothionein Type B Cluster Analogs: Synthesis, Structure, 1H NMR and ESI-MS” Inorg. Chem. 2022, 61, 19857-19869. DOI: 10.1021/acs.inorgchem.2c03088
Highlights:
- First metallothionein type B cluster with Cd3S3 metallocycle prepared outside of a protein
- Zn3S3 metallocycle prepared with same ligand provides third example outside of a protein
- Two oligomeric states found by NMR for recipitate analyzing as “Hg3L3(ClO4)3“
- Homotrimetallic clusters characterized by ESI-MS
- ESI-MS used to study fragmentation of heterotrimetallic clusters prepared in situ
Other coauthors include Haley M. Brennan (BS Chemistry W&M 2019), Sophia B. Bunnde (BS Chemistry W&M 2018), Qiaoyue Kuang (W&M undergraduate Fall 2016-Spring 2018), Tana V. Palomino (BS Chemistry W&M 2021), Joshua S. Sacks (BS Chemistry W&M 2019), Steven M. Berry (Camille & Henry Dreyfus Postdoctoral Fellow at W&M 2003-2005; currently Associate Professor and Chemistry Department Chair University of Minnesota Duluth), Raymond J. Butcher (crystallography collaborator from Howard University), and colleagues JC Poutsma and Robert D. Pike.
Updated February 2024