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Updated: Jun 26, 2025

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Asymmetric Synthesis of Quaternary α-Aryl Stereocentres in Benzofuran-3(2H)-Ones Using Decarboxylative Asymmetric
Fionn McNeill1, Brendan Twamley2, Patrick J Guiry1
1Centre for Synthesis and Chemical Biology, School of Chemistry, University College Dublin Belfield, Dublin 4, Ireland.
Abstract:
The Pd-catalysed decarboxylative asymmetric allylic alkylation (DAAA) has been applied to the enantioselective synthesis of sterically hindered benzofuran-3(2H)-one-derived α-aryl-β-keto esters employing the (R,R)-ANDEN phenyl Trost ligand. A range of substrates were synthesised, employing previously developed aryllead triacetate methodology to install various aryl groups. The resulting α-aryl-α-allyl benzofuran-3(2H)-one DAAA products were obtained in moderate to high yields and in enantioselectivities of up to 96 % ee, with the best results observed for substrates containing a di-ortho-substitution pattern on the aryl ring as well as naphthyl-containing substrates.
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