Synthesis of new trifluoromethyl-containing 1-(3,5-dialkyl-4-hydroxybenzyl)-pyrazole and -pyrazol-5-one deriatives and their corresponding aroxyls

Abstract

3,5-Dialkyl-4-hydroxybenzylhydrazine 1 reacted with hexafluoroacetylacetone and trifluoroacetylacetone yielding the pyrazoles 2 bearing trifluoromethyl and/or methyl substituents in positions 3 and 5. The same hydrazine derivatives 1 afforded the pyrazol-5-ones 3 with trifluoroacetoacetic acid ethyl ester. On oxidation with lead tetraacetate in CH2Cl2, some stable aroxyls were obtained and their ESR spectra are described.

Keywords

• fluorination
• pyrazole
• pyrazolone
• trifluoromethyl-1
• 3-diketones