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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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Intermolecular C(sp 3 )−H Amination of Complex Molecules
Abstract A general and operationally convenient method for intermolecular amination of C(sp3)−H bonds is described. This technology allows for efficient functionalization of complex molecules, including numerous pharmaceutical targets. The combination of pivalonitrile as a solvent, Al2O3as an additive, and phenyl sulfamate as a nitrogen source affords differential reaction performance and substrate scope. Mechanistic data strongly implicate a pathway for catalyst decomposition that initiates with solvent oxidation, thus providing rationale for the marked influence of pivalonitrile on this reaction process.
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- Award ID(s):
- 1700982
- PAR ID:
- 10055043
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 18
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 4956-4959
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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