Mass Spectra of 1,2,4-Oxadiazole-5-thiones and 1,2,4-Thiadiazole-5-ones

Abstract

The mass spectra of 3,4-disubstituted-1,2,4-oxadiazole -5(4H)-thione and 3,4-disubstituted-1,2,4-thiadiazole-5(4H) -ones have been studied. The rearrangement of molecular ion of 1,2,4-oxadiazole-5-thiones to 1,2,4-thiadiazole-5-ones was proposed. Some major fragments observed in the spectra were interpreted and the fragmentation patterns involving McLafferty rearrangements were reported.