CEA, DAM, DIF, F-91297, Arpajon, France.
J Mass Spectrom. 2013 Mar;48(3):306-11. doi: 10.1002/jms.3156.
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.
使用电喷雾电离在负离子模式下研究了爆炸物特屈儿（N-甲基-N，2，4，6-四硝基苯胺；Mw = 287 u）的反应性。在光谱中检测到的主要物质与在 m/z 318 处观察到的离子相对应（先前假定为奇数电子离子tetryl + HNO，C7H6O9N6）。在这项研究中，我们使用 D 标记结合高分辨率质谱表明，这种物质对应于一个偶数电子阴离子（即 C8H8O9N5），这是由于特屈儿与用作溶剂的甲醇之间形成了 Meisenheimer 配合物。在 CID 条件下，该配合物的碎裂揭示了一个意想不到的碎片：在 m/z 228 处形成 2,4,6-三硝基苯酚氧阴离子。(18)O 标记结合量子化学计算有助于我们更好地理解形成这种产物离子的反应途径和机制。这是通过一个过渡态发生的，导致 SN2 型反应，随后演变成离子偶极复合物。后者最终分解为去质子化的苦味酸。
