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Abstract We report copper(II) and copper(III) trifluoromethyl complexes supported by a pyridinedicarboxamide ligand (L) as a platform for investigating the role of electron transfer in C(sp2)−H trifluoromethylation. While the copper(II) trifluoromethyl complex is unreactive towards (hetero)arenes, the formal copper(III) trifluoromethyl complex performs C(sp2)−H trifluoromethylation of a wide range of (hetero)arenes. Mechanistic studies using the copper(III) trifluoromethyl complex suggest that the mechanism of arene trifluoromethylation is substrate‐dependent. When the thermodynamic driving force for electron transfer is high, the reaction proceeds through a previously unidentified single electron transfer (SET) mechanism, where an initial electron transfer occurs between the substrate and oxidant prior to CF3group transfer. Otherwise, a CF3radical release/electrophilic aromatic substitution (SEAr) mechanism is followed. These studies provide valuable insights into the role of strong oxidants and potential mechanistic dichotomy in Cu‐mediated C(sp2)−H trifluoromethylation.
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Bonding and the role of electrostatics in driving C–C bond formation in high valent organocopper compounds
The electronic structures and contrasting reactivity of [Cu(CF3)4]−and [Cu(CF3)3(CH3)]−were probed using coupled cluster andab initiovalence bond calculations.
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- Award ID(s):
- 1954515
- PAR ID:
- 10470610
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 59
- Issue:
- 1
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 98 to 101
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D2CC05865K
