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Catalytic reductive desymmetrization of malonic esters
1State Key Laboratory of Synthetic Chemistry, Department of Chemistry, The University of Hong Kong, Hong Kong, China.
Nature Chemistry
|June 11, 2021
Summary
A novel dinuclear zinc complex enables asymmetric reduction of malonic esters, creating chiral quaternary stereocenters. This method offers a powerful alternative for synthesizing complex molecules with high enantioselectivity.
Area of Science:
- Organic Chemistry
- Asymmetric Synthesis
- Catalysis
Background:
- Quaternary stereocenters are crucial motifs in many pharmaceuticals and natural products.
- Desymmetrization of prochiral substrates offers an efficient route to enantiomerically enriched compounds.
- Malonic esters are versatile building blocks due to their facile synthesis and functionalization.
Purpose of the Study:
- To develop a novel catalytic system for the desymmetrization of disubstituted malonic esters.
- To achieve highly enantioselective synthesis of α-quaternary β-hydroxyesters.
- To provide a practical alternative to existing desymmetrization methods.
Main Methods:
- Utilized a dinuclear zinc complex with a tetradentate ligand.
- Performed selective asymmetric hydrosilylation of one carbonyl group in malonic esters.
- Investigated the enantioselectivity and chemoselectivity of the reduction.
Main Results:
- Achieved excellent enantiocontrol in the desymmetrization of malonic esters.
- Demonstrated high chemoselectivity for the diester motif.
- Successfully synthesized a diverse range of α-quaternary β-hydroxyesters.
Conclusions:
- The developed dinuclear zinc complex provides a highly effective catalytic system for asymmetric synthesis.
- This method offers a valuable alternative for constructing quaternary stereocenters.
- The approach facilitates the synthesis of complex molecules with potential applications in medicinal chemistry.
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