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. 2022 Apr 13;27(8):2508.
doi: 10.3390/molecules27082508.

H-Bond Mediated Phase-Transfer Catalysis: Enantioselective Generating of Quaternary Stereogenic Centers in β-Keto Esters

Patryk Niedbała  1 , Maciej Majdecki  1 , Piotr Grodek  1 , Janusz Jurczak  1
Affiliations

H-Bond Mediated Phase-Transfer Catalysis: Enantioselective Generating of Quaternary Stereogenic Centers in β-Keto Esters

Patryk Niedbała et al. Molecules. .

Abstract

In this work, we would like to present the development of a highly optimized method for generating the quaternary stereogenic centers in β-keto esters. This enantioselective phase-transfer alkylation catalyzed by hybrid Cinchona catalysts allows for the efficient generation of the optically active products with excellent enantioselectivity, using only 1 mol% of the catalyst. The vast majority of phase-transfer catalysts in asymmetric synthesis work by creating ionic pairs with the nucleophile-attacking anionic substrate. Therefore, it is a sensible approach to search for new methodologies capable of introducing functional groups into the precursor's structure, maintaining high yields and enantiomeric purity.

Keywords: Cinchona catalysts; alkylation; enantioselectivity; organocatalysis; phase-transfer catalysis.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Cinchona phase-transfer catalysts A–O.
Figure 2
Figure 2
Model of a possible intermediate state for the reaction.
See this image and copyright information in PMC

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