Umetani, Shigeo published the artcileLiquid-liquid distribution of 4-acyl-3-methyl-1-phenyl-5-pyrazolones and their zinc complexes, Safety of 5-Methyl-2-phenyl-4-(2,2,2-trifluoroacetyl)-1H-pyrazol-3(2H)-one, the main research area is acylmethylphenylpyrazolone partition aqueous cyclohexane; zinc acylmethylphenylpyrazolone partition aqueous cyclohexane.
The distribution of 8 4-acyl-3-methyl-1-phenyl-5-pyrazolones and their Zn complexes between aqueous and cyclohexane phases was investigated. The acid dissociation constants and partition constants of the extractants were discussed in terms of a substituent effect. Two series of examined reagents in which one has an aromatic substituent at the 4-position of 5-pyrazolone, and the other an aliphatic one give similar extraction constants Since their acid dissociation constants are essentially the same, a relationship, log PMA = 2 log PHA + constant, is postulated. The extraction constant of a fluorinated reagent which has a considerably small pKa value is also similar to that of the reagents having aliphatic substituents.
Bulletin of the Chemical Society of Japan published new progress about Ionization. 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, Safety of 5-Methyl-2-phenyl-4-(2,2,2-trifluoroacetyl)-1H-pyrazol-3(2H)-one.
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics