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Stereoselective α-Chlorination of β-Keto Esters in the Presence of Hybrid Amide-Based Cinchona Alkaloids as Catalysts.

ABSTRACT: We report an enantioselective phase transfer α-chlorination of β-keto esters catalyzed by hybrid amide-based Cinchona derivatives. The chlorination process proceeds with proper quantitative yields (up to <99%) and high asymmetric induction (up to 97% ee). We show that the use of only 0.5 mol % hybrid catalyst based on a Cinchona core allows the chlorination reaction to be conducted in a highly enantioselective manner with various indanone and tetralone carboxylate esters.

SUBMITTER: Majdecki M

PROVIDER: S-EPMC7872425 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Stereoselective α-Chlorination of β-Keto Esters in the Presence of Hybrid Amide-Based Cinchona Alkaloids as Catalysts.

Majdecki Maciej M Grodek Piotr P Jurczak Janusz J

The Journal of organic chemistry 20201215 1

We report an enantioselective phase transfer α-chlorination of β-keto esters catalyzed by hybrid amide-based Cinchona derivatives. The chlorination process proceeds with proper quantitative yields (up to <99%) and high asymmetric induction (up to 97% ee). We show that the use of only 0.5 mol % hybrid catalyst based on a Cinchona core allows the chlorination reaction to be conducted in a highly enantioselective manner with various indanone and tetralone carboxylate esters. ...[more]

PMID: 33320665

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