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Updated: Jul 19, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Scalable methodology for the catalytic, asymmetric alpha-bromination of acid chlorides
Cajetan Dogo-Isonagie1, Tefsit Bekele, Stefan France
1Department of Chemistry, New Chemistry Building, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA.
Abstract:
The optimization of a practical, catalytic, asymmetric process for the alpha-bromination of acid chlorides to produce synthetically versatile, optically active alpha-bromoesters is reported. A range of products is produced in high enantioselectivity and moderate to good chemical yields with retention of both upon scale-up. The reactions herein are catalyzed by cinchona alkaloid derivatives, with the best performance achieved by the use of a proline cinchona alkaloid conjugate designed in a de novo fashion.
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