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Ruthenium-Catalyzed Tandem C-H Fluoromethylation/Cyclization of N-Alkylhydrazones with CBr3F: Access to 4-Fluoropyrazoles

Alexis Prieto, Didier Bouyssi* and Nuno Monteiro*

*Univ Lyon, Université Claude Bernard Lyon 1, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS, CNRS UMR 5246), F-69622 Villeurbanne, France, Email:,

A. Prieto, D. Bouyssi, N. Monteiro, J. Org. Chem., 2017, 82, 3311-3316.

DOI: 10.1021/acs.joc.7b00085

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A double C-H fluoroalkylation of readily available aldehyde-derived N-alkylhydrazones with tribromofluoromethane provides 4-fluoropyrazoles in a single step. RuCl2(PPh3)3 is a very efficient catalyst for this transformation.

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Key Words


ID: J42-Y2017