Synthesis 2005(15): 2583-2589  
DOI: 10.1055/s-2005-872078
PAPER
© Georg Thieme Verlag Stuttgart · New York

A Simple Synthesis of 6-Phenylpyrano[2,3-c]pyrazol-4(1H)-ones

Wilfried Becker, Gernot A. Eller, Wolfgang Holzer*
Department of Drug Synthesis, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
Fax: +43(1)42779556; e-Mail: wolfgang.holzer@univie.ac.at;
Further Information

Publication History

Received 14 February 2005
Publication Date:
20 July 2005 (online)

Abstract

A novel synthesis of substituted 6-phenylpyrano[2,3-c]pyrazol-4(1H)-ones via reaction of various 2-substituted or 2,5-disubstituted 2,4-dihydro-3H-pyrazol-3-ones with phenylpropyn­oyl chloride using calcium hydroxide in refluxing 1,4-dioxane is described. N-Unsubstituted representatives were obtained by treatment of 4-methoxybenzyl-protected congeners with trifluoroacetic acid.

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