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Updated: May 23, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Organocatalysis as a safe practical method for the stereospecific dibromination of unsaturated compounds
Gloria Hernández-Torres1, Bin Tan, Carlos F Barbas
1The Skaggs Institute for Chemical Biology and Department of Chemistry, The Scripps Research Institute, 10550 Torrey Pines Road, La Jolla, California 92037, USA.
Abstract:
Organocatalytic stereospecific dibromination of a wide variety of functionalized alkenes was achieved using a stable, inexpensive halogen source, 1,3-dibromo 5,5-dimethylhydantoin, and a simple thiourea catalyst at room temperature. The presence of a tertiary amine enhanced the rate of the dibromination reaction, and yields were good in various solvents, including aqueous solvents. The procedure was extended to alkynes and aromatic rings and to dichlorination reactions by using the 1,3-dichloro hydantoin derivative.
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