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Updated: Jan 29, 2026

Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Formal [4 + 2] Cycloadditions of Anhydrides and α,β-Unsaturated N-Tosyl Ketimines
Noah P Burlow1, Sara Y Howard1, Carla M Saunders1
1Department of Chemistry , University of California , One Shields Ave , Davis , California 95616 , United States.
Abstract:
A method for the diastereoselective synthesis of highly substituted β-enamino ketones from anhydrides and ketone-derived imines is reported. Cyclic, enolizable anhydrides undergo a base-promoted conjugate addition reaction with α,β-unsaturated N-tosyl ketimines, followed by an intramolecular acylation to give formal [4 + 2] cycloaddition products. The carboxylic acid-containing products are formed with modest selectivity for the cis-diastereomer and can be fully epimerized to the trans-diastereomer upon esterification.
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