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Updated: Mar 27, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Enantioselective reductive cyclization of alkynals via cobalt catalysis
Jing-Jing Zhu1, Min-Min Liu1, Ping Tian1
1The Research Center of Chiral Drugs, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, China. zhaoyw@shutcm.edu.cn.
None:
Transition metal-catalyzed asymmetric intermolecular reductive coupling of alkynes and aldehydes has been well-established for constructing chiral allylic alcohols. In contrast, the intramolecular variant remains underexplored. Herein, we present a cobalt-catalyzed reductive cyclization of alkynals, providing chiral 4-chromanols with high efficiency (83% average yield), good to excellent enantioselectivities (85-96% ee), and broad functional group tolerance. Moreover, preliminary bioactivity studies against human hepatocellular carcinoma cells have also been performed.
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