Mass spectra of indazolones and pyrazolones—II: 5-pyrazolones

✍ Scribed by J. M. Desmarchelier; R. B. Johns

• Book ID: 102964425
• Publisher: John Wiley and Sons
• Year: 1969
• Tongue: English
• Weight: 547 KB
• Volume: 2
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/oms.1210020704

✦ Synopsis

The m a s spectral fragmentations of 3-methyl-5-pyrazolone (I), 3-methyl-5-pyrazoloiie-1-d, (11), 3-methyl-5-pyrazolone-1,4,4-d3 (TII), l-acetyl-3-inethyl-5-pyrazolone (IV), 3-niethyl-5ethoxy-pyrazole (V), 3,4-dimethyl-5-pyrazolone (Vi), 1,3-dirnethyl-5-pyrazolone (VII), l-acetyl-5acetoxy-3,4-dimethylpyrazole (VIII), 1,2,3-trirnethyl-5-pyrazolone (IX), 3,4,4-trimethyl-5-pyrazoloiie (X), 3,4,4-trimethyl-5-pyrazolone-l-d, (XI), 3-phenyl-5-pyrazolone (Xii), 2-acetyl-3-phenyl-5pyrazolone (XIII) and 5-acctoxy-3-phenylpyrazole (XIV) are reported. Comparicon is niade between the mass spectra of 5-pyrazolones and 3-iiidazolones. As for the latter compounds initial loss of .N2R is preferred to loss of .CHO, and ic followed by loss of C O . The [M -11 ions are intense in the C-metliyl substituted pyrazolones, and unlike the 3-indazolones, the pyrazolones do not show any significant losc of HCN froni these ionc. The mass spcctra distingiiish betwecn certain isoiiieric 5-pyrazolones. * For Part 1, see Ref 1.