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Updated: Jun 3, 2025

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Hydrogen-Borrowing-Based Methods for the Construction of Quaternary Stereocentres
Jessica L Crompton1, Timothy C Jenkins1, Sam M Rowe2
1Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK.
Abstract:
Compounds containing quaternary stereocentres are a valuable motif in biologically active compounds. Herein we present our strategy to utilise the hydrogen borrowing manifold to access α-quaternary ketones via a tandem acceptorless dehydrogenation-cyclisation cascade. This new application of the methodology results in the formation of five- and six-membered carbocycles with a high degree of diastereoselectivity. Interestingly, benzylic alcohol substrates behaved anomalously and eliminated sulfinate in situ to give a set of rearranged α-quaternary ketone products.
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