Reactions in the mass spectrometry of 2,4,6‐ N ‐tetranitro‐ N ‐methylaniline (tetryl)

Despite the presence of the ions at m/z 242 and m/z 243 in the electron ionization (EI) and chemical ionization (CI) mass spectra of tetryl, respectively, no such daughter ions were observed in the collision‐induced dissociation spectra of the M + · ion in EI and of the [M+H] + ion in CI. This supports the thesis that these ions are formed through hydrolysis of tetryl to N‐methylpicramide in the ion source before ionization. It was found that the hydrolysis is considerably stronger under CI consitions, but can be minirnized in EI. The structure of the molecular ion at m/z 242 in the EI mass spectrum of N‐methylpicramide was found to be similar to that of the [MH‐NO 2 ] + ion in the CI mass spectrum of tetryl.