CONTRIBUTION TO THE STUDY OF 4-MONOSUBSTITUTED-3-AMINO-5-PYRAZOLONES

Abstract

The condensation of monosubstituted cyanoacetic esters with hydrazine gave rise to 4-R-3-amino-5-pyrazolones. The pyrazolones prepared were those in which R = o-chlorobenzyl, β-p-methylphenoxyethyl, γ-p-methylphenoxypropyl, β-p-ethylphenoxyethyl, β-p-chlorophenoxyethyl, γ-p-chlorophenoxypropyl, γ-p-bromophenoxypropyl, or n-dodecyl.The ultraviolet absorption spectra of these pyrazolones were determined in neutral, acid, and alkaline medium.