title: ESI formation of a Meisenheimer complex from tetryl and its unusual dissociation.
abstract: The reactivity of the explosive tetryl (N-methyl-N,2,4,6-tetranitroaniline; Mw = 287 u) was studied using electrospray ionization in negative mode. The main species detected in the spectrum corresponds to the ion observed at m/z 318 (previously assumed to be the odd-electron ion [tetryl + HNO](-•), C7H6O9N6). In this study, we show using D-labeling combined with high-resolution mass spectrometry that this species corresponds to an even-electron anion (i.e. C8H8O9N5), resulting from the formation of a Meisenheimer complex between tetryl and the methanol used as the solvent. Fragmentation of this complex under CID conditions revealed an unexpected fragment: the formation of a 2,4,6-trinitrophenoxide anion at m/z 228. (18)O-labeling combined with quantum chemical calculations helped us better understand the reaction pathways and mechanisms involved in the formation of this product ion. This occurs via a transition state leading to a SN2-type reaction, consequently evolving toward an ion-dipole complex. The latter finally dissociates into deprotonated picric acid.
authors.affiliation: CEA, DAM, DIF, F-91297, Arpajon, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Hubert
authors.forename: Héloïse
authors.initials: H
authors.lastname: Dossmann
authors.forename: Xavier
authors.initials: X
authors.lastname: Machuron-Mandard
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Tabet