Cyclic inorganic compounds. Part III. Hexameric bromophosphonitrile
Bromophosphonitriles prepared from phosphorus pentabromide and ammonium bromide in 1,1,2,2-tetrachloroethane are contaminated with chlorine-containing compounds. Pure products can be obtained from reactions in 1,2-dibromoethane, and in addition to the previously known (PNBr2)3, 4, and 5, dodecabromohexaphophonitrile, P6N6Br12, has been isolated. Possible configurations for twelve-membered P–N ring systems are discussed.