Dataset Information

Synergistic effects of CH₃CO₂H and Ca²⁺ on C-H bond activation by MnO₄.

ABSTRACT: The activation of metal-oxo species with Lewis acids is of current interest. In this work, the effects of a weak Brønsted acid such as CH₃CO₂H and a weak Lewis acid such as Ca²⁺ on C-H bond activation by KMnO₄ have been investigated. Although MnO₄ ^- is rather non-basic (pK _a of MnO₃(OH) = -2.25), it can be activated by AcOH or Ca²⁺ to oxidize cyclohexane at room temperature to give cyclohexanone as the major product. A synergistic effect occurs when both AcOH and Ca²⁺ are present; the relative rates for the oxidation of cyclohexane by MnO₄ ^-/AcOH, MnO₄ ^-/Ca²⁺ and MnO₄ ^-/AcOH/Ca²⁺ are 1 : 73 : 198. DFT calculations show that in the active intermediate of MnO₄ ^-/AcOH/Ca²⁺, MnO₄ ^- is H-bonded to 3 AcOH molecules, while Ca²⁺ is bonded to 3 AcOH molecules as well as to an oxo ligand of MnO₄ ^-. Our results also suggest that these synergistic activating effects of a weak Brønsted acid and a weak Lewis acid should be applicable to a variety of metal-oxo species.

SUBMITTER: Shi H

PROVIDER: S-EPMC9555569 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Synergistic effects of CH3CO2H and Ca2+ on C-H bond activation by MnO4.

Shi Huatian H Cheng Lin L Pan Yi Y Mak Chi-Keung CK Lau Kai-Chung KC Lau Tai-Chu TC

Chemical science 20220913 39

The activation of metal-oxo species with Lewis acids is of current interest. In this work, the effects of a weak Brønsted acid such as CH3CO2H and a weak Lewis acid such as Ca2+ on C-H bond activation by KMnO4 have been investigated. Although MnO4 - is rather non-basic (pK a of MnO3(OH) = -2.25), it can be activated by AcOH or Ca2+ to oxidize cyclohexane at room temperature to give cyclohexa ...[more]

PMID: 36320399

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Dataset Information

Synergistic effects of CH₃CO₂H and Ca²⁺ on C-H bond activation by MnO₄.

Publications

Synergistic effects of CH<sub>3</sub>CO<sub>2</sub>H and Ca<sup>2+</sup> on C-H bond activation by MnO<sub>4</sub>.

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