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Updated: Sep 15, 2025
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Palladium-Catalyzed Hydroalkynylation of 1,3-Dienes: Access to 1,5-Enynes
Xinni Qiu1, Ruize Ma1, Huanfeng Jiang1
1Key Laboratory of Functional Molecular Engineering of Guangdong Province, State Key Laboratory of Luminescent Materials and Devices, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
Abstract:
Herein, we report an efficient strategy for palladium-catalyzed hydroalkynylation of 1,3-dienes using haloalkynes (X = Cl, Br) as alkynylating reagents and HCOONa as an economical hydrogen donor, successfully constructing synthetically valuable 1,5-enyne skeletons. This method demonstrates operational simplicity, mild reaction conditions, and scalability. Mechanistic investigations revealed that the formation of a π-allyl Pd(II) intermediate effectively suppressed β-H elimination, endowing the reaction with excellent regioselectivity and chemoselectivity control. The application potential in complex molecule construction was validated through the diverse derivatization of products.
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