Arriau, J. published the artcileStudy by semiempirical methods on theoretical chemistry in the pyrazolone series. IV. Substituted derivatives of 1-phenyl-3-methylpyrazol-5-one, HPLC of Formula: 14580-22-4, the publication is Tetrahedron (1972), 28(23), 5725-38, database is CAplus.
The electronic spectrum of 1-phenyl-3-methylpyrazol-5-one was calculated by the semiempirical MO methods of complete neglect of differential overlap, Pariser-Parr-Pople, and Hueckel-ω. At long wavelengths the Ph groups gave 2 relatively weak bands, the pyrazolone ring showed an intense transition, and another strong band, only observed exptl. in solvents such as n-heptane, occurred at short wavelengths. Substituents in the Ph group influenced the spectra according to their nature and position. The effect of solvent was estimated quant.
Tetrahedron published new progress about 14580-22-4. 14580-22-4 belongs to pyrazoles-derivatives, auxiliary class Organic Pigment, name is 1-(2-Chlorophenyl)-3-methyl-5-pyrazolone, and the molecular formula is C10H9ClN2O, HPLC of Formula: 14580-22-4.
Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics