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Chalcogen-substituted carbenes: a density functional study of structure, stability, and donor ability
1Department of Chemistry, The University of Winnipeg 515 Portage Avenue Winnipeg MB R3B 2E9 Canada j.ritch@uwinnipeg.ca +1-204-774-2401 +1-204-786-9730.
RSC Advances
|June 7, 2023
Summary
Computational studies reveal that chalcogen-substituted carbenes, specifically N-heterocyclic carbenes (NHCs), show promise as ligands. These carbenes can stabilize unusual metal and main group compounds.
Area of Science:
- Organometallic Chemistry
- Computational Chemistry
Background:
- Chalcogen-substituted carbenes are an emerging class of compounds.
- Understanding their electronic structure and reactivity is crucial for applications.
Purpose of the Study:
- To computationally assess the stability and reactivity of chalcogenazol-2-ylidene carbenes (NEHCs).
- To evaluate their potential as ancillary ligands.
Main Methods:
- Density functional theory (DFT) was employed.
- Electronic structures, stability towards dimerization, and ligand properties were analyzed.
- A reference compound, 1,3-dimethylimidazol-2-ylidene, was studied for comparison.
Main Results:
- NEHCs exhibit electronic structures suitable for ligand applications.
- Their stability towards dimerization was evaluated.
- A computational method for assessing carbene ligand properties (σ-donor and π-acceptor) was presented.
Conclusions:
- Chalcogen-substituted carbenes are potentially valuable ancillary ligands.
- They can stabilize low-valent metals and paramagnetic main group molecules.
- The presented computational method offers an effective way to evaluate carbene ligand characteristics.
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