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Palladium (Pd)‐catalyzed radical oxidative C−H carbonylation of alkanes is a useful method for functionalizing hydrocarbons, but there is still a lack of understanding of the mechanism, which restricts the application of this reaction. In this work, density functional theory (DFT) calculations were carried out to study the mechanism for a Pd‐catalyzed radical esterification reaction. Two plausible reaction pathways have been proposed and validated by DFT calculations. The computational results reveal that the generated alkyl radical prefers to add to the carbon monoxide (CO) molecule to form a carbonyl radical before bonding with the Pd species. Radical addition onto Pd followed by CO migratory insertion was unfavorable owing to the high energy barrier of the migratory insertion step. The regioselectivity of the C(sp3)−H carbonylation was also investigated by DFT. The results show that the regioselectivity is controlled by both the bond dissociation energy of the reacting C−H bond and the stability of the corresponding generated carbon radical. Competitive side reactions also affected the yield and regioselectivity owing to the rapid consumption of the stable radical intermediate. Carbonylation mechanism: DFT method M06‐L was used to investigate the mechanism of Pd‐catalyzed radical oxidative carbonylation of alkanes with alcohols to afford alkyl acid esters. The results show alkyl radicals prefer to add to the CO molecule to form a carbonyl radical before bonding with the Pd species. Regioselectivity is controlled by both the bond dissociation energy of reacting the C−H bond and the stability of the corresponding generated carbon radical. [ABSTRACT FROM AUTHOR]

Density functional theory calculations were performed to study the counterion effect and directing group effect in rhodium mediated concerted metalation deprotonation type C H bond activation of arenes. The use of different carboxylates as counterions results in changes to the activation energies over a narrow range. These changes are mainly attributed to the opposing effects of alkalinity and nucleophilicity of the substituted groups. The effects of directing groups were also considered. By introducing directing groups, the C H bond activation energy is greatly reduced. Our results show that different directing groups have similar effects and activation energies. [ABSTRACT FROM AUTHOR]

Abstract: A highly para‐selective CAr−H difluoromethylation of ketoxime ethers under ruthenium catalysis has been developed. A wide variety of ketoxime ethers are compatible with the reaction, which leads to the corresponding para‐difluoromethylated products in moderate to good yield. A mechanistic study clearly showed that chelation‐assisted cycloruthenation is the key factor in the para selectivity of the difluoromethylation of ketoxime ethers. Density functional theory was used to gain a theoretical understanding of the para selectivity.# [ABSTRACT FROM AUTHOR]

A transition-metal-assistedoxidative C(sp3)-H/N–Hcross-coupling reaction of N-alkoxyamides with aliphatichydrocarbons is described. During the reaction, nitrogen radicalswere generated from the oxidation of N-alkoxyamides.Experiments and DFT calculations revealed that transition-metal catalystcould lower the reactivity of the generated nitrogen radical by thecoordination of the transition metal, which allowed the selectiveradical/radical cross-coupling with the transient sp3carbonradical to construct C(sp3)–-N bonds. Various C(sp3)–H bonds could be transformed into C(sp3)–N bonds through this radical amidation strategy. [ABSTRACT FROM AUTHOR]