5-Nitro-2H-tetrazole (5) was prepared from 5-amino-1H-tetrazole (1) through diazotization and Sandmeyer reaction. 5 was then reacted with formaldehyde to form 5-nitro-2-hydroxymethyl-tetrazole (6), and 6 was reacted with concentrated HCl or HBr to form 5-chlorotetrazole (7) and 5-bromotetrazole (8), respectively. Their structures were characterized by MS, IR, ¹H NMR and ¹³C NMR techniques, and the crystal structures of 5-nitrotetrazole sodium salt (4), 5 and 6 were determined by X-ray single crystal diffraction analysis. 4 belongs to triclinic system with space group P-1; 5 and 6 belong to monoclinic system with space group P2₁, and the crystal parameters of 6 were a＝0.66131(18) nm, b＝0.54905(15) nm, c＝0.7566(2) nm, Z＝2, V＝0.27470(13) nm³, D_c＝1.754 g/cm³, F(000)＝128, μ＝0.160 mm^－1.

Key words: nitrotetrazole, synthesis, crystal structure, reactivity