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Observation of electrochemically generated nitrenium ions by desorption electrospray ionization mass spectrometry.

ABSTRACT: We report the observation of the electrochemically generated nitrenium ions of 4,4'-dimethyoxydiphenylamine and di-p-tolylamine in solution by mass spectrometry. This setup takes inspiration from desorption electrospray ionization mass spectrometry to sample directly from the surface of a rotating waterwheel working electrode for mass spectrometric analysis. Detection of the 4,4'-dimethyoxydiphenylamine nitrenium ion was expected based upon para-methoxy resonance stabilization, whereas observation of the di-p-tolylamine nitrenium ion might be unexpected because resonance stabilization from the para-substituted position is unavailable. However, the short timescale analysis of the setup allows for the isolation of the di-p-tolylamine nitrenium ion, which is electrogenerated in solution and detected mass spectrometrically.

SUBMITTER: Brown TA

PROVIDER: S-EPMC5518571 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Observation of electrochemically generated nitrenium ions by desorption electrospray ionization mass spectrometry.

Brown Timothy A TA Hosseini-Nassab Niloufar N Chen Hao H Zare Richard N RN

Chemical science 20151008 1

We report the observation of the electrochemically generated nitrenium ions of 4,4'-dimethyoxydiphenylamine and di-<i>p</i>-tolylamine in solution by mass spectrometry. This setup takes inspiration from desorption electrospray ionization mass spectrometry to sample directly from the surface of a rotating waterwheel working electrode for mass spectrometric analysis. Detection of the 4,4'-dimethyoxydiphenylamine nitrenium ion was expected based upon <i>para</i>-methoxy resonance stabilization, whe ...[more]

PMID: 28791096

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