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Updated: Jun 25, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Catalyst-Controlled Divergent Annulation Reactions of Allenoates and Fully Substituted 1,3-Indandione Derived
Wu-Dong Yu1, I-Ting Chen1, Ting-Hung Chu1
1Department of Chemistry, National Chung Hsing University, Taichung 402202, Taiwan.
Abstract:
Two catalyst-controlled, regiodivergent annulation protocols for allenoates with fully substituted 1,3-indandione derived electron-deficient alkenes have been developed, furnishing a series of spiroindane-1,3-diones and 3,4-dihydro-2H-pyran derivatives in high yields. Plausible mechanistic pathways for both annulation reactions are proposed: spiroindane-1,3-diones are obtained via a [3 + 2] annulation, while 3,4-dihydro-2H-pyran derivatives arise from a [4 + 2] annulation.
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