The Structure of +. and + Ions Formed from Vinylimidazoles, Studied by Collisionally Activated Dissociation Mass Spectrometry

Article abstract of DOI:10.1002/oms.1210190105

Mass spectra of the three isomeric vinylimidazoles have been compared and the structures of the fragment ions ^+. and ⁺ have been investigated by collisionally activated dissociation mass spectrometry.The greater part of the non-decomposing ions m/z 68 from 2-vinylimidazole and from 2-imidazolecarboxylic acid methyl ester, and a minor part of this ion formed from the free acid, all have the same structure: the imidazole ring system, with hydrogens at both nitrogen atoms but none at C(2).An analogous structure, with an ethynyl group at C(2), is proposed for the m/z 93 ion from 2-vinylimidazole.