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Updated: Dec 27, 2025
Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Nucleophilic Substitution at Quaternary Carbon Stereocenters
Veeranjaneyulu Lanke1, Ilan Marek1
1Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City 3200009, Haifa, Israel.
Abstract:
Cyclopropyl carbinol derivatives undergo a regio- and stereoselective nucleophilic substitution at the quaternary carbon center, with pure inversion of configuration, to provide the acyclic products as a single diastereomer. The selectivity of the substitution is attributed to the existence of a cyclobutonium species, reacting at the most substituted carbon center. Diastereomerically pure and enantiomerically enriched tertiary alkyl bromide, chloride, ester, and fluoride could therefore be easily prepared in only three catalystic steps from commercially available alkynes.
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