Premium
Determination of active hydrogen in organic compounds by electron‐impact mass spectrometry
Author(s) -
Dinya Zoltán,
Lipták Miklós,
Szabó Pál,
Sztaricskai Ferenc,
Vékey Karoly
Publication year - 1992
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.1290061110
Subject(s) - chemistry , mass spectrometry , analyte , mass spectrum , deuterium , hydrogen , ammonium , electron ionization , ion , analytical chemistry (journal) , thermolabile , inorganic chemistry , ammonium chloride , organic chemistry , chromatography , ionization , physics , enzyme , quantum mechanics
Abstract We report here detailed studies of Bose et al. 's ( J. Org. Chem. 47, 4008 (1982)) simple method for obtaining electron‐impact (EI) mass spectra from non‐volatile and/or thermolabile organic compounds by using ammonium salts. Good quality mass spectra can be obtained by mixing the analyte with different ammonium salts (mainly with NH 4 Cl) in a given ratio, the mixture being introduced through a conventonal direct probe. A wide variety of ammonium salts has been used to study the effect of the anion and to determine the optimum analyte:NH 4 X ratio and the other experimental parameters (i.e., electron energy, source temperature etc). A very simple and cheap means of determination of active hydrogen in hydroxyl, carboxyl, sulfhydryl, amino and amido etc groups by EI mass spectrometry using deuterated ammonium chloride (ND 4 CI) is described. The method is based on exchange of active hydrogen for deuterium occurring in situ in the ion source. This technique allows drect comparison of spectra before and after deuteration and the number of active hydrogens can be identified in most cases. The applicability of this method is demonstrated on different model compounds.