Electron impact-induced rearrangements in compounds having the PS bond

Abstract

The fragmentation processes of P=S compounds upon electron impact include the following bond-forming reactions :(i) molecular ion rearrangement of the type -P(:S)O-R -P(:O)S-R, (ii) bond formation between substituents (especially aryl groups) on phosphorus, (iii) loss of SH. from the molecular ion where the hydrogen can be derived from an alkyl or an aryl group, and (iv) hydrogen rearrangement to give the phenol molecular ion (or an isomer) in compounds having a phenoxy-substituent.THE propensity of organosulphur compounds to undergo rearrangement upon electron impact and the fact that bond-forming reactions involving atoms other than hydrogen have been observed in ph~sphines,~, phosphine o x i d e ~, ~' ~ phosphites,4 phosphate^,^ and phosphonates t i led us to examine the mass spectra of compounds (1)-(XII). Methyl and aryl substituents were preferred to larger alkyl groups since hydrogen rearrangements, which are common ' in the spectra of phosphorus compounds containing alkyl substituents, could obscure the more interesting skeletal rearrangement processes.

Mass spectral characterization of the CWC‐related isomeric dialkyl alkylphosphonothiolates/alkylphosphonothionates under gas chromatography/mass spectrometry conditions

“…The typical EI‐induced gas phase 'thiono‐thiolo rearrangement', i.e., conversion of > P(S)‐O‐R into > P(O)‐S‐R, has been observed in many classes of phosphorus‐containing compounds such as phosphines, phosphates, phosphonates and phosphoramidates, etc . Cooks et al .…”

Electron impact mass spectrometry of phenyl thiophosphoroorganic amides

“…The compounds studied were methyl phenyl phosphinomorpholinylamidothioate (l), O-methyl phenyl phosphonomorpholinylamidothioate (2), phenyl phosphonomorpholinylamidochloridothioate (3) and O-ethyl phenyl phosphonomorpholinylamidothioate (4).…”

Component Analysis of the Commercial Metal Extractant, Cyanex 302®, by GC–MS

“…In general, P=S compounds tend to loss S and SH · . 11,[16][17][18] In this sense, the loss of SH · from the molecular ion, where the hydrogen can be derived from the methyl group, is also observed:…”

“…This rearrangement was not observed in the spectrum of its dithio analogue, whereas in the case of the methyl ester of bis(2,4,4-trimethylpentyl)phosphinic acid it gave rise to the base peak. 15 Isomerization of the molecular ion R2-P(:S)O-CH3 to give R2-P(:O)S-CH3 apparently precedes the rearrangement, 11 group originates the ion at m/z = 207. However, an alternative process could be the loss of a methyl group from the molecular ion, to give the base peak at m/z = 305, followed by the loss of a C7H14 fragment.…”