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Updated: Mar 30, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
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Enantioselective Alkyne Addition to Aliphatic, Aromatic, and Vinyl Aldehydes Using Zn, (i)PrI, H8BINOL, and
Wen-Cai Huang1,2, Winnie Liu2, Xue-Dan Wu2
1Department of Pharmaceutical and Bioengineering, School of Chemical Engineering, Sichuan University , Chengdu, China 610065.
Abstract:
A new catalytic system based on the readily available Zn, (i)PrI, H8BINOL, and Ti(O(i)Pr)4 has been developed which avoids the use of pyrophoric ZnEt2. It can effectively catalyze the reaction of various terminal alkynes with aromatic, aliphatic, and vinyl aldehydes to generate chiral propargylic alcohols at room temperature with up to 98% yield and 98% enantiomeric excess. This new system signifciantly expands the substrate scope of the previously reported system using Zn, EtI, BINOL, and Ti(O(i)Pr)4.
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