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Updated: Apr 11, 2026
Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Enantioselective Synthesis of Quaternary Stereocenter Aldehydes by Palladium-Catalyzed Intermolecular Propargylation
Shuaijie Wu1, Xiaomeng Xu2, Tian Tang1
1School of Chemistry and Materials, Yangzhou University, Yangzhou, Jiangsu 225002, China.
Abstract:
A highly efficient palladium-catalyzed enantioselective α-propargylation of α-alkyl-α-aryl disubstituted aldehydes with propargylic acetates has been developed using BINOL-derived chiral phosphoramidite ligands. This protocol affords a series of enantioenriched aldehydes bearing all-carbon quaternary stereocenters in moderate to good yields with high enantioselectivities. The reaction features a broad substrate scope, mild reaction conditions, facile scalability, and versatile downstream transformations. Density functional theory (DFT) calculations were conducted to elucidate the reaction mechanism and the origin of the enantioselectivity.
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