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Abstract Transition metal‐catalyzed C−H bond oxidation of free carboxylic acid stands as an economic, selective, and efficient strategy to generate lactones, hydroxylated products, and acetoxylated products and attracts much of the chemists’ attention. Herein, we performed a density functional theory study on the mechanism and selectivity in Pd‐catalyzed and MPAA ligand‐enabled C−H bond acetoxylation reaction. It was found that the ligand, base, and substrate are important in determining the reaction mechanism and the selectivity. The acetic anhydride additive is critical in leading the reaction to be acetoxylation, instead of the lactonization, through a facile σ‐bond metathesis mechanism that leads to the Pd‐OAc in‐termediate. Our study sheds light on the further development of transition metal‐catalyzed C−H bond oxidation reactions.
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“Catch and release” of the Cp N3 ligand using cobalt: dissociation, protonation, and C–H bond thermochemistry
Coordination of the amine-rich CpN3ligand to cobalt is reported. Ligand displacement leads to ligand protonation and evaluation of the metal-free C–H bond thermochemistry, revealing a weak homolytic C–H bond dissociation free energy (52 kcal mol−1).
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- Award ID(s):
- 2055097
- PAR ID:
- 10541013
- Publisher / Repository:
- The Royal Society of Chemistry
- Date Published:
- Journal Name:
- Dalton Transactions
- ISSN:
- 1477-9226
- 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/D4DT01560F
