Complexes of Dimethylaminophosphazenes with Metal Ions

The preparation of complexes DDPN.2MCl 2 (M = Mn, Fe, Co, Zn ), DDPN.M(NO 3 ) 2 , (M = Mn, Co, Ni, Cu, Zn), (DDPN = N 6 P 6 (NMe 2 ) 12 ) ), and N 9 P 9 (NMe 2 ) 18 .2CoCl 2 is described. All the complexes of the hexamer are of the high spin type and contain the cations DDPNMX + (X = Cl, NO 3  ). Their infrared and electronic spectra show that their molecular structures are essentially the same as those established crystallographically for the chlorocations (M = Co, Cu ), in which, as a consequence of steric interactions, the metal has a distorted trigonal-bipyramidal environment. The complex with Cu(NO 3 ) 2 is exceptional in that the DDPNCu 2+ ion is formed in ionizing solvents, with a change in the stereochemistry of the metal. Coordination localizes π-electrons in nitrogen, weakens the ring bonds, and strengthens the exocyclic P—N bonds, as expected theoretically. Approximate values of ligand field parameters of the Co(NO 3 ) 2 and Ni(NO 3 ) 2 complexes are similar to those of complexes formed by simple amines; the phosphazenes act as σ-donors, their acceptor levels not being used significantly.