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Mass spectrometric behaviour of 1‐imino‐substituted pyrazolo[1,2‐ a ]‐[1,2,4]triazoles under electron and chemical ionization
Author(s) -
Joutsiniemi Karoliina,
Vainiotalo Pirjo,
Morgenstern Olaf,
Klemann Anke
Publication year - 1997
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570340204
Subject(s) - chemistry , chemical ionization , electron ionization , isobutane , mass spectrum , reagent , adduct , ion , fragmentation (computing) , ionization , mass spectrometry , acetone , deuterium , organic chemistry , physics , quantum mechanics , computer science , catalysis , operating system , chromatography
The spectra of five pharmacologically interesting substituted pyrazolo[1,2‐ a ][1,2,4]triazole hydroiodides were measured under electron and chemical ionization. In the electron ionization spectra, in addition to the intense molecular ion peak of the free base (M + *), there was also a relatively intense molecular ion peak of the hydroiodide form, which is unusual since the hydroiodides are rarely so stable. The phenylimino and phenylamino substituents of the triazole ring affected the fragmentation behaviour of the compounds very much. The chemical ionization reagent gases used in this work were methane, isobutane, deuterated ammonia and acetone. In all the cases practically only [M+H] + ions were observed, the only exception being acetone which also gave rise to intense [M+C 2 H 3 O] + and [M + C 3 H 7 O] + adduct ions. None of the reagent gases used was able to cause any fragmentation.