Azides of Iron III

The complex hexaazidoferrate(III), [Fe (N3)6] , forms stable salts with large organic cations. These compounds are soluble in polar organic solvents, such as acetone, nitrobenzene, dimethylformamide, and pyridine contact with water aquates the complex. Isolated were the tris-(trimethylbenzylammonium) salt, MP 107°C, the tris-(p-nitrobenzylpyridinium) salt, MP 112°C and the sodium bis-(tetramethylammonium) salt, MP 270°C with deflagration [155]. 

finely ground iron(III) sulfate is suspended in absolute methanol and agitated with dry sodium azide. The solution turns deep red it is decanted and evaporated in vacuo to yield black-brown, leafy crystals of Fe(N3)3 [54]. Reactions in aqueous media, e.g., dissolving iron metal in hydrazoic add [153] or treating iron(III) salts with sodium azide [135], lead upon concentration to poorly defined basic products. 

Formation of iron(III) azide was also observed by electrolyzing a solution of ammonium azide in liquid ammonia with an iron anode. The characteristic red color appeared near the anode, but no product was isolated [154]. 

---