Electron attachment to tetrazoles: The influence of molecular structure on ring opening reactivity

The electron-induced reactivity of 5-(4-chlorophenyl)-1H-tetrazole and 5-chloro-1-phenyl-1H-tetrazole was studied using a trochoidal electron monochromator quadrupole mass spectrometer experimental setup. 5-(4-chlorophenyl)-1H-tetrazole underwent dissociative electron attachment to form Cl^-, [M-HCl]^-, and [M-H]^-. 5-chloro-1-phenyl-1H-tetrazole underwent associative electron attachment to form the parent anion and dissociative electron attachment to form Cl^-, CN₂Cl^-, [M-N₂-Cl]^-, and [M-HCl]^-. For each anion product, the ion yield was measured as a function of incident electron energy. Density functional theory calculations were performed to support the experimental results with estimates of the energetic thresholds for the different reaction pathways. While the tetrazole group is susceptible to electron-induced ring opening in both molecules, this process was only observed for 5-chloro-1-phenyl-1H-tetrazole, indicating that this process is influenced by the structure of the molecule.