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Updated: Aug 1, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Copper-Catalyzed Enantioselective Borylative Allyl-Allyl Coupling of Allenes and Allylic gem-Dichlorides
Martín Piñeiro-Suárez1, Andrés M Álvarez-Constantino1, Martín Fañanás-Mastral1
1Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
Abstract:
A catalytic asymmetric reaction between allenes, bis(pinacolato)diboron, and allylic gem-dichlorides is reported. The method involves the coupling of a catalytically generated allyl copper species with the allylic gem-dichloride and provides chiral internal 1,5-dienes featuring (Z)-configured alkenyl boronate and alkenyl chloride units with high levels of chemo-, regio-, enantio-, and diastereoselectivity. The synthetic utility of the products is demonstrated with the synthesis of a range of optically active compounds. DFT calculations reveal key noncovalent substrate-ligand interactions that account for the enantioselectivity outcome and the diastereoselective formation of the (Z)-alkenyl chloride.
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