Cage and Complex Ring Phosphazanes

A bicyclic cage derivative, P4(NMe)6, can be made below 20°C from methylamine and phosphorus trichloride (7.287). This compound is insoluble in water but soluble in many organic solvents. A highly symmetrical adamantane-type cage structure is indicated by both x-ray analysis and by NMR which shows a single resonance peak. 

The cage molecule P4(NMe)6 reacts with hydrogen chloride to give PCI3. 

The isopropyl derivative P4(NPr )e can have an alternative cage structure (7.289). On further heating this reverts to the more stable adamantane-type structure (7.287) [24]. 

FIGURE 7.7 Cage structure of P404(NMe)6. Filled circles, P lined circles, N open cirlces. Me. 

The bicyclic hydrazinodiphosphine (7.290a) can be made from tris (dimethylamino)phosphine and sym-dimethyl hydrazinium hydrochloride (7.291). Compounds (7.290b,c) are also known and (7.292) is strongly basic [25]. 

---