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Updated: Oct 25, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Synergistic Substrate- and Condition-Controlled Switching between Alkene and Alkyne: A [4 + 2] Strategy for Diverse
Ke-Ji Li1,2, Zi-Qiang Yan1, You Zhou1
1College of Chemical Engineering, Hubei University of Arts and Science, Xiangyang441053, China.
Abstract:
A substrate- and condition-controlled chemoselectivity switching strategy is developed for the [4 + 2] cycloaddition to construct isoindolinone derivatives. Leveraging the electronic differences between alkenes and alkynes, this approach enables precise modulation of reaction pathways, affording diverse substitution patterns without transition metal catalysts. The protocol features high atom economy, excellent chemoselectivity, and operational simplicity, providing a green and efficient route to an important heterocyclic scaffold.
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