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Updated: Mar 11, 2026
A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Selective Tsuji-Trost type C-allylation of hydrazones: a straightforward entry into 4,5-dihydropyrazoles
El Hachemia El Mamouni1, Martin Cattoen2, Marie Cordier3
1Laboratoire de Synthèse Organique, CNRS, Ecole Polytechnique, ENSTA ParisTech-UMR 7652, Université Paris-Saclay, 828 Bd des Maréchaux, 91128, Palaiseau, France. laurent.elkaim@ensta-paristech.fr and Laboratoire de Chimie Organique, Institute of Chemistry, Biology and Innovation (CBI)-ESPCI Paris/CNRS (UMR8231)/PSL Research University, 10 rue Vauquelin, 75231 Paris Cedex 05, France.
Abstract:
The 4,5-dihydropyrazole motif has drawn considerable attention over the years as it was shown to exhibit a plethora of biological and pharmacological properties, including anticancer, antibacterial, antifungal, antiviral, and anti-inflammatory properties. As such, it has been the target of a number of methods and drug discovery programs. We report here a straightforward and highly selective approach featuring a key palladium-catalysed Tsuji-Trost type C-allylation and subsequent intramolecular 1,4-addition of hydrazones.
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