Abstract
Fast atom bombardment (FAB) mass spectrometric behavior of hydrochlorides of basic compounds has been studied with the aid of collisionally activated dissociation (CAD) and metastable ion (MI) spectra. The FAB mass spectrum of guanidine hydrochloride showed the cluster ions, [n(M · HC1) + M + H]+(n = 1, 2, 3~), where M and HC1 are a guanidine molecule and hydrogen chloride, respectively. The FAB mass spectra of various hydrochlorides of basic compounds (M · HC1) were obtained and some compounds produced these cluster ions but some did not produce them. The CAD and MI spectra of the cluster ions from hydrochlorides of mono-, di-, and trimethylamine, and mono-, di-, and triethylamine were obtained in order to know the characteristics of these cluster ions. HC1 loss (from [n(M · HC1) + M + H]+) ions appeared and the relationship between the HC1 loss ion intensity and cluster number (n) suggests that HC1 loss from the cluster ions depends on the molecular structure of compounds. The ion [M · HC1 + H]+ was not observed in the FAB mass spectra, but only appeared in the CAD spectra from [(M · HC1) + M + H]+ when M was monomethylamine, dimethylamine, and monoethylamine.
