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Updated: Apr 19, 2026
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A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
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Enantioselective α-Amination Enabled by a BINAM-Derived Phase-Transfer Catalyst.
H M Nelson1, J S Patel1, H P Shunatona1
1Department of Chemistry, University of California, Berkeley, California 94720, United States.
Chemical Science
|December 9, 2014
Summary
Chiral phase-transfer catalysis enables highly enantioselective alpha-amination of carbonyl compounds using aryldiazonium salts. BINAM-derived phosphoric acids are key to achieving high stereoselectivity in this valuable synthetic transformation.
Area of Science:
- Organic Chemistry
- Asymmetric Catalysis
Background:
- Enantioselective synthesis of alpha-amino carbonyl compounds is crucial for pharmaceuticals.
- Developing efficient catalytic methods for C-N bond formation remains a challenge.
Purpose of the Study:
- To develop a highly enantioselective alpha-amination of carbonyl compounds.
- To explore the use of chiral anion phase-transfer catalysis for this transformation.
Main Methods:
- Utilized chiral anion phase-transfer of aryldiazonium cations.
- Employed BINAM-derived phosphoric acids as catalysts.
- Applied the method to indanone- and benzosuberone-derived substrates.
Main Results:
- Achieved highly enantioselective alpha-amination of carbonyl compounds.
- Demonstrated broad substrate scope including indanone and benzosuberone derivatives.
- Confirmed the critical role of BINAM-derived phosphoric acids in high enantioselectivity.
Conclusions:
- Chiral anion phase-transfer is an effective strategy for enantioselective alpha-amination.
- The developed method provides access to valuable alpha-amino acid derivatives.
- This approach offers a new route for synthesizing chiral amines.
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