Synthesis 2022; 54(20): 4529-4538
DOI: 10.1055/s-0040-1719937
paper

Synthesis of 3-Aryl-Substituted 4-Aminopyrazoles from Acetophenones

,
Di Xu
,
Tyler A. Tuck
,
Haiming Zhang


Abstract

A synthetic methodology for a protecting-group-free formation of 3-aryl-substituted 4-aminopyrazoles from acetophenones via a telescoped oximation and hydrazine condensation of 1,3-ketoaldehydes to generate nitrosopyrazoles, and copper-catalyzed NaBH4 reduction of the nitroso group, was demonstrated. The synthesis tolerates a broad scope of substrates with a variety of substituents on the phenyl ring to afford the desired products.

Supporting Information



Publication History

Received: 23 December 2021

Accepted after revision: 31 May 2022

Article published online:
26 July 2022

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