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Abstract An anionic Rh−Ga complex catalyzed the hydrodefluorination of challenging C−F bonds in electron‐rich aryl fluorides and trifluoromethylarenes when irradiated with violet light in the presence of H2, a stoichiometric alkoxide base, and a crown‐ether additive. Based on theoretical calculations, the lowest unoccupied molecular orbital (LUMO), which is delocalized across both the Rh and Ga atoms, becomes singly occupied upon excitation, thereby poising the Rh−Ga complex for photoinduced single‐electron transfer (SET). Stoichiometric and control reactions support that the C−F activation is mediated by the excited anionic Rh−Ga complex. After SET, the proposed neutral Rh0intermediate was detected by EPR spectroscopy, which matched the spectrum of an independently synthesized sample. Deuterium‐labeling studies corroborate the generation of aryl radicals during catalysis and their subsequent hydrogen‐atom abstraction from the THF solvent to generate the hydrodefluorinated arene products. Altogether, the combined experimental and theoretical data support an unconventional bimetallic excitation that achieves the activation of strong C−F bonds and uses H2and base as the terminal reductant.
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This content will become publicly available on October 15, 2026
Pd-catalyzed desulfonylative fluorination of electron-deficient (hetero)aryl sulfonyl fluorides
Pd catalysis is used to convert electron-deficient (hetero)aryl sulfonyl fluorides to the corresponding (hetero)aryl fluorides with extrusion of SO2.
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- Award ID(s):
- 2202693
- PAR ID:
- 10645100
- Publisher / Repository:
- The Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 16
- Issue:
- 40
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 18936 to 18941
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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