Diphosphazane dioxide

Coordination compounds of diphosphazane dioxides with uranyl or thorium ions were synthesized [475], The crystal structure of [U02(N03)2L1] [L, = Ph2P(0) N(Ph)P(0)Ph2] reveal the bidentate chelating mode of binding of the diphosphazane dioxide to these metals. The chemistry of other uranium organophosphorus and related compounds is described [476-479]. Some of the actinide complexes are presented in Table 5.16. 

Diphosphazane dioxide complexes of lanthanides have potential application in the solvent extraction separation of lanthanides. Reaction of lanthanide nitrate with X2P(0)NPr )-P(0)X2(L-L) yields the bis chelate complexes Ln(NC>3)(L-L)2. The structure of the praseodymium complex has been determined by X-ray diffraction and the space group is P32- There are two independent molecules in the unit cell which differ in orientation of the phenyl group. The metal ion is ten-coordinated [264]. 

New unsymmetrical diphosphazanes (57) have been prepared and converted into mono-and dioxides or sulfides. These compounds have been characterised by NMR and variable-temperature NMR measurements. Some of the... 

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