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Updated: Jun 18, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Catalytic, enantioselective, conjugate alkyne addition
Thomas F Knöpfel1, Pablo Zarotti, Takashi Ichikawa
1Laboratorium für Organische Chemie, ETH Hönggerberg, CH-8093 Zürich, Switzerland.
Abstract:
We document a copper-catalyzed, enantioselective, conjugate addition involving the direct use of a terminal acetylene, which undergoes in situ metalation. The addition reactions of phenylacetylene to Meldrum's acid derived acceptors take place in aqueous media, without recourse to inert atmosphere. The success of the enantioselective process was enabled by the use of a new class of conveniently accessed P,N-ligands, which we have termed PINAP. These modular ligands are responsive to numerous electronic and steric modifications that permit optimization of the reaction.
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