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What ion is generated when ionizing acetonitrile?

Giulia de Petris·Simonetta Fornarini·Maria Elisa Crestoni·Anna Troiani·Paul M Mayer
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Abstract

It has long been assumed that ionizing neutral acetonitrile produces ions with the same atomic connectivity, CH(3)CN(+*). Recent calculations on the C(2)H(3)N(+*) potential energy surface have suggested that it may be difficult to generate pure CH(3)CN(+*) when ionizing acetonitrile. We have probed the interconversion of CH(3)CN(+*) and its lower energy isomer CH(2)CNH(+*) by calculation, collision-induced dissociation mass spectrometry and ion-molecule reaction. The latter ion, ionized ketenimine, is co-generated upon electron or chemical ionization of neutral acetonitrile in the ion source of a mass spectrometer. An estimate of the ratio of the two isomers can be obtained from their respective ion-molecule reactions with CO(2) or COS. CH(3)CN(+*) reacts by proton-transfer with CO(2) and charge transfer with COS, whereas CH(2)CNH(+*) is unreactive.

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AcetonitrilesChemistry, PhysicalElectronsIonsKineticsMass SpectrometrySpectrum AnalysisLetterResearch Support, Non-U.S. Gov't

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Giulia de Petris, Simonetta Fornarini, Maria Elisa Crestoni, Anna Troiani, Paul M Mayer. 2005-05-26. What ion is generated when ionizing acetonitrile?. https://doi.org/10.1021/jp051484u

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