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Updated: Aug 3, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Cobalt-Catalyzed Efficient Convergent Asymmetric Hydrogenation of E/Z-Enamides
Tiantian Chen1,2, Yashi Zou3, Yanhua Hu3
1Key Laboratory for Thin Film and Microfabrication Technology of the Ministry of Education, School of Electronics, Information and Electrical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China.
Abstract:
Using the diphosphine-cobalt-zinc catalytic system, an efficient asymmetric hydrogenation of internal simple enamides has been realized. In particular, the Ph-BPE ligand can achieve convergent asymmetric hydrogenation of E/Z-substrates. High yields and excellent enantioselectivities were obtained for both acyclic and cyclic enamides bearing α-alkyl-β-aryl, α-aryl-β-aryl, and α-aryl-β-alkyl substituents. Hydrogenated products can be applied for the synthesis of useful chiral drugs such as Arfromoterol, Rotigotine, and Norsertraline. In addition, reasonable catalytic mechanism and stereocontrol mode are proposed based on DFT calculations.
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