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Updated: Nov 1, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Phosphine-Catalyzed Intermolecular Dienylation of Alkynoate with para-Quinone Methides
Zefeng Song1, Weijia Wang1, Zhixin Liu1
1Molecular Synthesis Center, Key Laboratory of Marine Drugs, Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 23 Hongkong East Road, Qingdao 266071, Shandong Province, China.
Abstract:
An interesting remote δ-C 1,6-addition and an isomerization cascade reaction for phosphine-catalyzed activated alkynes have been disclosed. The products featuring a functional diene and a 1,1-diaryl methyl motif have been obtained in moderate to good yields (30-86%) by applying para-quinone methides (p-QMs) and δ-substituted alkynoate with tributylphosphine (PBu3) catalysis, along with high regioselectivity and stereoselectivity (dr > 20:1). The wide scope of compatible substrates (35 examples), such as indolyl, oxindolyl, ester, and cinnamyl, expand the utility of this methodology. A plausible mechanism and some applications of it have also been presented.
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