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Updated: Jun 28, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
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Synthesis of 1,3-Enynes by Iron-Catalyzed Propargylic C-H Functionalization: An Alkyne Analogue for the Eschenmoser
Shalini Dey1, Aaron D Charlack1, Austin C Durham1
1Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
Abstract:
A two-step protocol for the conversion of alkyl-substituted alkynes to 1,3-enynes is reported. In this α-methenylation process, an iron-catalyzed propargylic C-H functionalization delivers tetramethylpiperidine-derived homopropargylic amines which undergo facile Cope elimination upon N-oxidation to afford the enyne products. A range of aryl alkyl and dialkyl acetylenes were found to be suitable substrates for this process, which constitutes an alkyne analogue for the Eschenmoser methenylation of carbonyl derivatives. In addition, a new bench-stable precatalyst for iron-catalyzed propargylic C-H functionalization is reported.
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