User:A. T. Galenitis/sandbox/Octachlorotetraphosphazene

Octachlorotetraphosphazene is an inorganic compound with the formula (NPCl2)4. The molecule has a cyclic, unsaturated backbone consisting of alternating phosphorus and nitrogen centers, and can be viewed as a tetramer of the hypothetical compound N≡PCl2.

The compound has not been studied as much as the related species hexachlorotriphosphazene, in the samples of which octachlorotetraphosphazene is usually found as an unwanted contamintant.

Structure and bonding
Octachlorotetraphosphazene has a P4N4 core with six equivalent P–N bonds.

Synthesis

 * NH4Cl +  PCl5  →  1/n (NPCl2)n  +  HCl

Substitution at P
Some spiro-, ansa-, and spiro-ansa-cyclic derivatives have been prepared via nucleophilic substitution of octachlorotetraphosphazene with alkoxides.