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Updated: Apr 12, 2026
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Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
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Trap-Free Halogen Photoelimination from Mononuclear Ni(III) Complexes
Seung Jun Hwang1, David C Powers1, Andrew G Maher1
1†Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|May 8, 2015
Summary
Researchers achieved high yields in endothermic chlorine photoelimination reactions using nickel complexes. This breakthrough in halogen photoelimination advances energy storage cycles and bond activation strategies.
Area of Science:
- Inorganic Chemistry
- Photochemistry
- Materials Science
Background:
- Halogen photoelimination reactions are key to energy storage cycles.
- Activating strong chemical bonds often requires overcoming thermodynamic barriers.
- 3d metal complexes typically have short-lived excited states, limiting their reactivity.
Purpose of the Study:
- To report high-yielding, endothermic chlorine photoelimination from mononuclear nickel complexes.
- To elucidate the mechanism of ligand-assisted halogen elimination.
- To explore strategies for activating challenging bonds using ancillary ligands.
Main Methods:
- Time-resolved spectroscopy
- Steady-state photocrystallography
- Synthesis of mononuclear Ni(III) complexes
Main Results:
- Achieved high yields in Cl2 photoelimination reactions.
- Demonstrated an endothermic reaction pathway.
- Proposed a mechanism involving ligand-assisted halogen elimination.
Conclusions:
- Ligand-assisted halogen elimination is a viable strategy for Ni(III) complexes.
- This approach can overcome limitations of short-lived excited states in 3d metal complexes.
- Enables activation of thermodynamically challenging bonds for energy storage applications.
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