Jensen, Bror Skytte published the artcileSynthesis of 1-phenyl-3-methyl-4-acyl-5-pyrazolones, Name: 5-Methyl-2-phenyl-4-(2,2,2-trifluoroacetyl)-1H-pyrazol-3(2H)-one, the main research area is .
cf. CA 56, 6718d. Condensations of acid chlorides and anhydrides with 1-phenyl-3-methyl-5-pyrazolone in dioxane, catalyzed by suspended Ca(OH)2, give directly and in good yield the following 4-acyl-l-phenyl-3-methyl-5-pyrazolone analogs, which are promising chelating agents for the extraction of metal ions (acyl group, m.p., and % yield given): Ac, 58° (MeOH-H2O), 56; EtCO, 62° (MeOH-H2O), 50; ClCH2CO, 88° (MeOH-H2O) (enol m. 140°), 73; PrCO, 80° (MeOH-H2O), 57; EtOCO, 122° (MeOH-H2O) (enol m. 72°), 46; p-BrC6H4CO, 167° (dioxane-H2O) (enol m. 122°), 82; p-O2NC6H4CO, 200° (dioxane-H20), 79; and F3CCO, 144° (EtOH-H2O) (enol m. 132°), 78. Also prepared is 50% 1-(p-nitrophenyl)-3-methyl-4-benzoyl-5-pyrazolone, m. 174° (keto), 224° (enol) (dioxane-H2O). The method fails to give a product capable of metal extraction with pivalyl chloride. The acid strength of the 4-acylpyrazolones is of the same magnitude as that of carboxylic acids (pK 3-5). Their mol. weights are determined by titration in H2O-alc. with phenolphthalein indicator.
Acta Chemica Scandinavica published new progress in CAplus about 1691-93-6, 1691-93-6 belongs to class pyrazoles-derivatives, name is 5-Methyl-2-phenyl-4-(2,2,2-trifluoroacetyl)-1H-pyrazol-3(2H)-one, and the molecular formula is C12H9F3N2O2, Name: 5-Methyl-2-phenyl-4-(2,2,2-trifluoroacetyl)-1H-pyrazol-3(2H)-one.
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics