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Grigor'eva, A. A.; Shainyan, B. А.; Kaurova, G. I.; Gracheva, E. I.; Lesnevskaya, N. B.; Barabanov, V. G.

doi:10.1023/a:1020708111882

Cited by 2 publications

(1 citation statement)

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“…As expected, the 19 F NMR spectrum of trans - 1 is very similar to that of its lower homologue trans - 2 , but showed clear evidence for the replacement of the trifluoromethyl group by a perfluoroethyl moiety (Figure ). Not surprisingly, the multiplicities of the various peaks in the spectrum also match very well with the corresponding signals in the 19 F NMR spectrum of perfluoroethylcyclohexane . The CF 3 group appears as a quartet because the expected 4 J coupling to the fluorine attached to C4 is accompanied by through space 5 J coupling, , of similar size, to the axial fluorine atoms at C3 and C5.…”

Section: Resultssupporting

confidence: 64%

Characterization of Nine Isomers in Commercial Samples of Perfluoroethylcyclohexanesulfonate and of Some Minor Components Including PFOS Isomers

Stefanac¹,

McCrindle

McAlees³

et al. 2018

Environ. Sci. Technol.

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Electrochemical fluorination of 4-ethylbenzenesulfonyl halides produces a mixture of compounds that has found extensive use as an erosion inhibitor in aircraft hydraulic fluids. This paper reports a study of the composition of commercial samples of this material from two industrial scale manufacturers in terms of the structures and relative concentrations of their components, the major of which is perfluoroethylcyclohexanesulfonate (PFECHS). Fractionation of one of these mixtures by column chromatography produced fractions in which all significant components were of sufficient purity to allow assignment of their structures by F NMR spectroscopy. Assessment of the relevant signals in theF NMR spectra of the commercial mixtures by integration revealed the presence of 14 constituents at levels ≥0.5% in terms of molar contributions. Ten of these involve five pairs of geometric isomers, including cis- and trans-PFECHS which accounted for between 55% and 60% of the components present. Three constituents were determined to be isomers of perfluorooctanesulfonate (PFOS), two branched and the other linear PFOS itself. The availability of samples of the various components also allowed us to identify the compounds responsible for the peaks observed when the commercial samples were analyzed by LC/MS using either C or perfluorophenyl stationary phases.

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