Reactions of polycyclic aromatic hydrocarbon radical cations with model biological nucleophiles

Andy B. Whitehill, M. George, Michael L. Gross

Research output: Contribution to journalArticlepeer-review

3 Scopus citations


The determination of gas-phase reactivity of a series of polycyclic aromatic hydrocarbons (PAHs) with nucleophiles is directed at achieving isomer differentiation through ion-molecule reactions and collisionally activated decomposition spectra. A series of PAH isomers form gas-phase [adduct - H]+ ions with the reagent nucleophiles pyridine and N- methylimidazole. Collisionally activated decomposition spectra of the [adduct - H]+ ions of the pyridine/PAH systems are dominated by products formed by losses of C5H4N, C5H5N (presumably neutral pyridine), and C5H6N. Collisional activation of PAH/N-methylimidazole [adduct- H]+ ions causes analogous losses of C4H5N2, C4H6N2 (presumably neutral N- methylimidazole), and C4H7N2. The relative abundances of the ions that result from these losses are highly isomer specific for N-methylimidazole but less so for pyridine. Furthermore, PAH/N-methylimidazole [adduct - H]+ ions undergo a series of metastable-ion decompositions that also provide highly isomer-specific information. The C4H7N2 (from PAH/N-methylimidazole product ions) and C5H6N (from PAH/pyridine product ions) losses tend to increase with the ΔH(f) of the PAH radical cation. In addition, it is shown that the fragmentation patterns of these gas-phase PAH/nucleophile adducts are similar to fragmentation patterns of PAH/nucleoside adducts generated in solution, which suggests that the structures of products formed in gas-phase reactions are similar to those produced in solution.

Original languageEnglish
Pages (from-to)628-638
Number of pages11
JournalJournal of the American Society for Mass Spectrometry
Issue number7
StatePublished - Jul 1996


Dive into the research topics of 'Reactions of polycyclic aromatic hydrocarbon radical cations with model biological nucleophiles'. Together they form a unique fingerprint.

Cite this