p-Toluenesulfonic acid → 5-(3-Methyl-4-nitro-phenyl)-2,4-dihydro-pyrazol-3-one

Participants

Reaction Steps

To an ethanol solution of ethyl 3-(3-methyl-4-nitro-phenyl)-3-oxo-propionate (3.0 g), hydrazine monohydrate (0.9 g) and a small amount of p-toluenesulfonic acid were added and the mixture was refluxed for 5 hours. After cooling, the solvent was distilled off under the reduced pressure and the obtained residue was purified by silica gel column chromatography to obtain 5-(3-methyl-4-nitro-phenyl)-2,4-dihydro-pyrazol-3-one (2.6 g). mp; 218-219° C.

Provenance & Evidence