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Gas-Phase Reactions of Dimethyl Disulfide with Aliphatic Carbanions - A Mass Spectrometry and Computational Study.

ABSTRACT: Ion-molecule reactions of Me₂S₂ with a wide range of aliphatic carbanions differing by structure and proton affinity values have been studied in the gas phase using mass spectrometry techniques and DFT calculations. The analysis of the spectra shows a variety of product ions formed via different reaction mechanisms, depending on the structure and proton affinity of the carbanion. Product ions of thiophilic reaction (m/z 47), S_N2 (m/z 79), and E2 elimination - addition sequence of reactions (m/z 93) can be observed. Primary products of thiophilic reaction can undergo subsequent S_N2 and proton transfer reactions. Gibbs free energy profiles calculated for experimentally observed reactions using PBE0/6-311+G(2d,p) method show good agreement with experimental results. Graphical Abstract ?.

SUBMITTER: Franczuk B

PROVIDER: S-EPMC5838211 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Gas-Phase Reactions of Dimethyl Disulfide with Aliphatic Carbanions - A Mass Spectrometry and Computational Study.

Franczuk Barbara B Danikiewicz Witold W

Journal of the American Society for Mass Spectrometry 20180108 3

Ion-molecule reactions of Me2S2 with a wide range of aliphatic carbanions differing by structure and proton affinity values have been studied in the gas phase using mass spectrometry techniques and DFT calculations. The analysis of the spectra shows a variety of product ions formed via different reaction mechanisms, depending on the structure and proton affinity of the carbanion. Product ions of thiophilic reaction (m/z 47), SN2 (m/z 79), and E2 elimination - add ...[more]

PMID: 29313204

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