Combined Trapped Ion Mobility and Infrared Ion Spectroscopy Study of Protonation Sites in Aromatic Amines.

ABSTRACT: The protonation site of aromatic amines in the gas phase has been under substantial debate, as it involves a subtle competition between the higher electronegativity of the amine nitrogen and the better charge delocalization ability of the fused aromatic rings. Previous studies have unambiguously shown, especially by ion mobility measurements, that higher-energy tautomers are easily observed depending on the experimental conditions in the ion source, including voltage settings and the type of solvent used in spray sources. Here, we use a combination of ion mobility and ion spectroscopy and focus on the tautomeric structure after ion mobility separation, in particular for protonated 1-aminonaphthalene and 1-aminoanthracene. We employ an atmospheric pressure chemical ionization (APCI)

SUBMITTER: Finazzi L 

PROVIDER: S-EPMC12412157 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature