Compounds of P, N and H Only

2 COMPOUNDS OF PHOSPHORUS, NITROGEN AND HYDROGEN 7.2.1 Compounds of P, N and H Only [1-13] 

Numerous compounds based on N, P and H are possible in principle. Those based on a single P atom and containing only P-N and N-H bonds include those listed in Table 7.3 although most of them remain hypothetical compounds. Some have, however, been characterised as polymers or as H-substituted derivatives. 

The cyclic trimer, (PNCl2)3 (7.319a) will react with liquid ammonia in a sealed tube to give the fully ammoniated derivative PN(NH2) 3. The action of heat on this latter compound first produces a form of phospham in which the trimeric rings probably remain intact (7.28), but this eventually loses more ammonia and decomposes along the route (7.27). The normal form of phospham, made from PCI5 and NH3 probably has a random network structure (7.30), like the product from reaction (7.29). 

Polymeric phosphorus amide inide is produced directly by reacting phosphorus trichloride with ammonia in ethereal solution at -20°C. 

If PCI3 is added to a saturated solution of NH3 in chloroform at -78°C, water-soluble phosphorus triamide is produced (7.32). On the other hand, if an excess of PCI3 is added rapidly to liquid NH3, the reaction goes according to (7.33), giving an amorphous red/yellow product. 

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