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Updated: Nov 9, 2025

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Direct α-Tertiary Alkylations of Ketones in a Combined Copper-Organocatalyst System
Ayako Kurose1, Yuto Ishida1, Goki Hirata1
1Graduate School of Science and Engineering, Yamaguchi University, 2-16-1 Tokiwadai, Ube, Yamaguchi, 755-8611, Japan.
Abstract:
Herein, we report an efficient method for the tertiary alkylation of a ketone by using an α-bromocarbonyl compound as the tertiary alkyl source in a combined Cu-organocatalyst system. This dual catalyst system enables the addition of a tertiary alkyl radical to an enamine. Mechanistic studies revealed that the catalytically generated enamine is a key intermediate in the catalytic cycle. The developed method can be used to synthesize substituted 1,4-dicarbonyl compounds containing quaternary carbons bearing various alkyl chains.
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