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Updated: Jun 10, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Direct catalytic asymmetric conjugate addition of terminal alkynes to alpha,beta-unsaturated thioamides
Ryo Yazaki1, Naoya Kumagai, Masakatsu Shibasaki
1Institute of Microbial Chemistry, Tokyo, 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan.
Abstract:
Direct catalytic asymmetric conjugate addition of terminal alkynes to alpha,beta-unsaturated thioamides under proton transfer conditions is described. Soft Lewis acid/hard Brønsted base cooperative catalysis is crucial for simultaneous activation of terminal alkynes and thioamides, affording the beta-alkynylthioamides in a highly enantioselective manner. Control experiments suggested that the intermediate copper thioamide enolate can work as Brønsted base to drive the catalytic cycle via proton transfer. The divergent transformation of the thioamide functionality highlights the synthetic utility of the alkynylation products.
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