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Updated: Apr 11, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Lewis-Acid-Promoted Divergent Synthesis of Cyclopentenes and Butanolides from Allyl Sulfides and Electron-Deficient
Dinesh Kumar Gopalakrishnan1, Daksh Singh Davas1, Janakiram Vaitla1
1Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
Abstract:
A Lewis-acid-promoted cascade reaction between allyl sulfides and electron-deficient alkynes has been developed for the synthesis of cyclopentenes and butanolides under mild Lewis acidic conditions. The transformation proceeds through thia-Michael addition followed by a [3,3]-sigmatropic rearrangement and intramolecular cyclization. The nature of the ester substituent on the allyl sulfide governs pathway divergence, selectively producing either cyclopentenes through all-carbon cyclization or butanolides via oxa-cyclization with excellent diastereoselectivity.
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