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4-Dimethylaminopyridine-Catalyzed Metal-Free Aerobic Oxidation of Aryl ?-Halo Esters to Aryl ?-Keto Esters.

ABSTRACT: A novel, metal-free aerobic oxidation method is described. 4-Dimethylaminopyridine (DMAP) successfully catalyzed the oxidation of aryl ?-halo esters to corresponding aryl ?-keto esters (up to 95% yield) under mild reaction conditions (Li2CO3, dimethylacetamide, air, and room temperature). A mechanism has been proposed where the oxidation proceeds through a [3 + 2] cycloaddition between O2 in an air atmosphere and pyridinium ylides. The ylides are supposedly generated from aryl ?-halo esters and DMAP in the presence of carbonates. Based on the plausible mechanism, the potential of DMAP as a catalyst in oxidation reactions was extended.

SUBMITTER: Jung Y

PROVIDER: S-EPMC7495759 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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4-Dimethylaminopyridine-Catalyzed Metal-Free Aerobic Oxidation of Aryl α-Halo Esters to Aryl α-Keto Esters.

Jung Yeonghun Y Hong Jee Eun JE Baek Seung Tae ST Hong Suckchang S Kwak Jae-Hwan JH Park Yohan Y

ACS omega 20200902 36

A novel, metal-free aerobic oxidation method is described. 4-Dimethylaminopyridine (DMAP) successfully catalyzed the oxidation of aryl α-halo esters to corresponding aryl α-keto esters (up to 95% yield) under mild reaction conditions (Li2CO3, dimethylacetamide, air, and room temperature). A mechanism has been proposed where the oxidation proceeds through a [3 + 2] cycloaddition between O2 in an air atmosphere and pyridinium ylides. The ylides are supposedly gener ...[more]

PMID: 32954144

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