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Abstract Although most class (b) transition metals have been studied in regard to CH4activation, divalent silver (AgII), possibly owing to its reactive nature, is the only class (b) high‐valent transition metal center that is not yet reported to exhibit reactivities towards CH4activation. We now report that electrochemically generated AgIImetalloradical readily functionalizes CH4into methyl bisulfate (CH3OSO3H) at ambient conditions in 98 % H2SO4. Mechanistic investigation experimentally unveils a low activation energy of 13.1 kcal mol−1, a high pseudo‐first‐order rate constant of CH4activation up to 2.8×103 h−1at room temperature and a CH4pressure of 85 psi, and two competing reaction pathways preferable towards CH4activation over solvent oxidation. Reaction kinetic data suggest a Faradaic efficiency exceeding 99 % beyond 180 psi CH4at room temperature for potential chemical production from widely distributed natural gas resources with minimal infrastructure reliance.
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Selective Activation of the C−H Bond in Methane by Single Platinum Atomic Anions
Abstract Mass spectrometric analysis of the anionic products of interaction between platinum atomic anions, Pt−, and methane, CH4and CD4, in a collision cell shows the preferred generation of [PtCH4]−and [PtCD4]−complexes and a low tendency toward dehydrogenation. [PtCH4]−is shown to be H−Pt−CH3−by a synergy between anion photoelectron spectroscopy and quantum chemical calculations, implying the rupture of a single C−H bond. The calculated reaction pathway accounts for the observed selective activation of methane by Pt−. This study presents the first example of methane activation by a single atomic anion.
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- Award ID(s):
- 1664182
- PAR ID:
- 10102462
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 58
- Issue:
- 23
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 7773-7777
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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