Premium
Electron ionization mass spectrometry of phenylpyridazinylmethanols and phenylpyridazinyl ketones
Author(s) -
Pittenauer Ernst,
Allmaier Günter,
Schmid Erich R.,
Krenmayr Peter,
Heinisch Gottfried,
Budzikiewicz H.
Publication year - 1991
Publication title -
rapid communications in mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.528
H-Index - 136
eISSN - 1097-0231
pISSN - 0951-4198
DOI - 10.1002/rcm.1290050909
Subject(s) - chemistry , fragmentation (computing) , electron ionization , ketone , ion , mass spectrum , collision induced dissociation , dissociation (chemistry) , mass spectrometry , polyatomic ion , fast atom bombardment , nitrogen atom , ionization , chemical ionization , medicinal chemistry , ring (chemistry) , tandem mass spectrometry , organic chemistry , chromatography , computer science , operating system
The mass spectrometric fragmentation behaviour of four monosubstituted pyridazines (phenyl‐3‐ and phenyl‐4‐pyridazinylmethanol, phenyl‐3‐pyridazinyl and phenyl‐4‐pyridazinyl ketone) was investigated. Fragmentation pathways were established by combined interpretation of the data obtained from high resolution measurements and from low‐energy collision‐activated dissociation mass spectra of the molecular ions as well as of several important fragment ions. A clear differentiation between these 3‐ and 4‐substituted 1,2‐diazines is possible for both sets of pyridazines. Only the spectra of the 3‐isomers exhibit an abundant [MH] + peak, which indicates a cyclization of these ions involving one ring nitrogen atom. Another difference between the two isomeric phenylpyridazinylmethanols is the loss of OH from the molecular ion, as detected for the C‐3 substituted compound only. For the phenylpyridazinyl ketones, the loss of CO from the molecular ion, which is only observed with the 3‐isomer, permits an unequivocal differentiation.