New possibilities of dimethylformamide dimethylacetal as a derivatization agent for gas chromatography/mass spectrometry analysis
- Authors: Zenkevich I.G.1, Pushkareva T.I.1
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Affiliations:
- Institute of Chemistry
- Issue: Vol 71, No 14 (2016)
- Pages: 1341-1351
- Section: Articles
- URL: https://journals.rcsi.science/1061-9348/article/view/182242
- DOI: https://doi.org/10.1134/S1061934816140161
- ID: 182242
Cite item
Abstract
It is shown that the use of dimethylformamide dimethylacetal for the derivatization of analytes in gas chromatography/mass spectrometry cannot be restricted by the known conversion of carboxylic acids, phenols, and thiols into their methyl esters (ethers), as well as by the conversion of non-volatile amino acids (and C-amino compounds of other classes) into their dimethylaminomethylene derivatives. The application of this reagent to the derivatization of hydrazine derivatives and volatile carbonyl-containing analytes is considered. In the last case, the reaction proceeds selectively via CH2 and/or CH3 groups in the α-position to the carbonyl fragment. The principal predestination of the derivatization of such analytes is their characterization by differences of gas-chromatographic retention indices (ΔRI) of reaction products and initial substrates. The ranges of variation of such increments, ΔRI, appeared to be different for different subgroups of carbonyl compounds; this allowed us to determine their structures more precisely. The mass spectra of C-dimethylaminomethylene derivatives of some carbonyl compounds, preferably 2-substituted 1-methyl- and 1-aryl-3-(dimethylamino) prop-2-en-1-ones, revealed intense [M–17] peaks. The appearance of these signals can be explained by the migration of a hydrogen atom and the formation of [М–ОН]+ ions.
About the authors
I. G. Zenkevich
Institute of Chemistry
Author for correspondence.
Email: izenkevich@mail15.com
Russian Federation, Petrodvorets, St. Petersburg, 198504
T. I. Pushkareva
Institute of Chemistry
Email: izenkevich@mail15.com
Russian Federation, Petrodvorets, St. Petersburg, 198504