Mass spectrometry and structure of heterocyclic ions by collisional activation.

The fragmentation of isomeric dimethylnitroindolizines due to electron impact was studied by collisional activation and high resolution mass spectroscopy. The M-OH]⁺ ion which is formed as a result of the ortho-effect was found to have a variable structure. In the case of 2,8-dimethyl-1-nitroindolizine, one of the main fragmentation processes of M-OH]⁺ is the elimination of an H₂O molecule.For Communication 2, see 1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 331–336, March, 1989.