Related Experiment Video
Updated: Jul 4, 2026

Using a Cyclic Ion Mobility Spectrometer for Tandem Ion Mobility Experiments
Published on: January 20, 2022
Identification of the aromatic tertiary N-oxide functionality in protonated analytes via ion/molecule reactions in
Penggao Duan1, Todd A Gillespie, Brian E Winger
1Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA.
Abstract:
A mass spectrometric method is presented for the rapid identification of compounds that contain the aromatic N-oxide functional group. This method utilizes a gas-phase ion/molecule reaction with 2-methoxypropene that yields a stable adduct for protonated aromatic tertiary N-oxides (and with one protonated nitrone) in different mass spectrometers. A variety of protonated analytes with O- or N-containing functional groups were examined to probe the selectivity of the reaction. Besides protonated aromatic tertiary N-oxides and one nitrone, only three protonated amines were found to form a stable adduct but very slowly. All the other protonated analytes, including aliphatic tertiary N-oxides, primary N-oxides, and secondary N-oxides, are unreactive toward or react predominantly by proton transfer with 2-methoxypropene.
Related Concept Videos
Mass Spectrometry: Aromatic Compound Fragmentation
Mass Spectrometry of Amines
Mass Spectrometry: Amine Fragmentation
In amines, the number of nitrogen atoms affects the mass of the molecular ion, which is described by the nitrogen rule of mass spectrometry. This rule states that a compound containing a single or...
Mass Spectrum: Interpretation
Mass Spectrometry: Overview
NMR Spectroscopy of Aromatic Compounds

