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The fragmentation of some alkyl thio‐phosphate esters by electron‐impact
Author(s) -
Santoro E.
Publication year - 1973
Publication title -
organic mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.475
H-Index - 121
eISSN - 1096-9888
pISSN - 0030-493X
DOI - 10.1002/oms.1210070509
Subject(s) - chemistry , mass spectrum , electron ionization , fragmentation (computing) , ion , thio , ionization , radical , oxygen , mass spectrometry , analytical chemistry (journal) , oxygen atom , alkyl , metastability , spectral line , medicinal chemistry , molecule , organic chemistry , chromatography , physics , astronomy , computer science , operating system
The mass spectra of the following compounds have been studied:and the fragmentation pathways established with the aid of accurate mass measurements, metastable transition and appearance potential determination. The mass spectra show that the sulphur‐containing compounds (II to IV) give a stronger molecular ion that that of compound I. A further significant difference is the low intensity, in the mass spectra of II to IV, of the fragments relative to the processes that occur in I, probably because the electron removed upon ionisation belongs to the sulpher atom in compounds II to IV and to the oxygen in compound I. The isomeric compounds, (III and IV) show quite different mass spectra, The radicals containing only Phosphorus and oxygen have an ionisation potential close to 9 eV and the presence of sulphur considerably lowes this value. The measured ionisation potentials of compounds I to IV are respectively, 10·7 0 , 9·5 5 , 9·2 0 and 9·0 0 eV. The heats of formation of compounds II and III have been estimated as −176 and −118 Kcal mole −1 , respectively.