Rrdttctiori of ~-rritrarri~rre-tctrazole.-A 25% aqueous solution of 5-nitramine-tetrazole was diluted with its own volume of glacial acetic acid, and excess of zinc dust was added and the temperature maintained at 60" for ten minutes. After decantation from excess zinc, the resultant solution gave, after agitation with benzaldehyde, a colourless precipitate which, after thorough washing in air, gave a positive acridine-hydrochloride spot test for zinc ion. A micro-estimation of zinc was made. (Found: Zn, 26. I, 26.2. C,H,N,Zn requires Zn, 26.0%.) Benzylidenetetrazolyl hydrazone (m.p., 2339 was obtained on prolonged digestion of the zinc derivative in dilute HCI.
Action of acidified potassiran iodide on iiitrogctargdazide.-Potassium iodide crystals were dissolved in 20 ml. of a standard azide solution containing 0.3084 g. azide per 50 ml. On acidification and boiling, iodine equivalent to 28.7 ml. 1-40 N/20 sodium thiosulphate was liberated. The end-point to the thiosulphate titration was not very sharp.
(Equivalent of azide with respect to iodine liberation, 61.25. Theory for 2 atoms iodine/mol. azide, 65.)
Actioii of alkali or1 rritrogrmr~lac~~e.-Nitroguanylazide solution (5 mi.), containing 0.3084 g. per 50 ml. solution, on titration with I -1.1 Nj2o carbonate-free alkali, with phenolphthalein as indicator, gave a sharp end-point after the addition of 7.9 ml. alkali. (Equivalent with respect to alkali: 68.5. Repetitions of this experinent gave values for the equivalent which varied between 68 and 69.5.) bteractiori of silver riitratc arid disodiiitii irirrarriirie tetrazok-0.961 N/zo AgNO:, (60 ml.) was added to disodium nitramine tetrazole solution (20 ml.), containing 0.2464 g. per 50 ml. The gelatinous precipitate immediately formed was separated and in a Volhard titration the filtrate gave a sharp end-point after the addition of 36.1 ml. 1 . 0 N / ~o NHJNS. (Equivalent with respect to interaction with AgNO, : 91.6. Theory requires Similar experiments with nitroguanyl a i d e gave much higher values for the equivalent which varied with the relative molar ratios of the AgNO, and azide employed.
hteracrioti of tiirrogitartyl azidr arid sihcr rriiraie after cqitivalertt
Nitroguanyl azide solution (5 ml., containing 0.3084 g. per 50 ml.) was, exactly neutralized with 7.9 ml. 1.14 N/2o alkali and I o N1. o AgNO, (20 ml.) was then added. Immediately a white gelatinous precipitate separated. On filtration the filtrate required 9.3 ml. 1.0 N/20 NI-I,CNS.