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Updated: Nov 20, 2025

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
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Theoretical Analysis of the Heterocyclic [4+2] Cycloaddition Between Pyridinium Ion and Enol Ether

Masataka Nakahara1, Kengo Hanaya1, Takeshi Sugai1

  • 1Department of Pharmaceutical Sciences, Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo, 105-8512, Japan.

Chemistryopen
|January 19, 2021
PubMed

Keywords:
[4+2] cycloadditiondensity functional theorypyridiniumreaction mechanismstepwise

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