Our previous work was the first to report [M+CH]+ and [M+C2H3]+ ions in the self ion-molecule reactions (SIMR) of two aza-crown ethers in an ion trap mass spectrometer (ITMS). In this study, the CH and C2H3 addition ions were also found in the SIMR of dopamine. The SIMR of dopamine lead to the formation of the protonated molecules ([M+H]+), of adduct ions ([M+F]+, where F represents fragment ions), and of [M+CH]+, [M+C2H3]+ and [2M+H]+ ions. Based on the combination of the results of isolation experiments and semi-empirical calculations, the reactive site for the formation of the [M+H]+ and [M+CH]+ ions of dopamine is proposed to be the amino group.
Rapid Communications in Mass Spectrometry 17(13), pp.1479-1482