CHEMISTRY OF TETRAAZAPENTALENES

2,4,8, 10-Tetranitrobenzotriazolo[2, 1-alpha]benzotriazole (TACOT), al though thermally very stable and insensitive as an explosive, is susce ptible to attack by nucleophiles. Reaction with azide ion results in d isplacement of nitro groups at the 4,10-positions, treatment with meth oxide ion effects displacement of the hydrogen atom at the 1-position and scission of the remote triazole ring, while ''vicarious nucleophil ic amination'' displaces all the aromatic hydrogens. 3,5,7-Trinitro-1, 3,3-triazolo[2, 1-alpha]benzotriazole and ,7-trinitro-1,2,3-triazolo[1 ,2-alpha]benzotriazole are prepared readily by nitration of the parent triazolobenzotriazoles. However they are thermally less stable than T ACOT and more sensitive to initiation by impact. Furthermore, attempte d further nitration and reaction with nucleophiles such as azide and m ethoxide ions both effect scission of the triazole ring to leave 4,6-d initrobenzotriazole.