Synthetic, spectroscopic, and structural Studies on Lanthanide Complexes of Diphosphazane Dioxide Ligands

Abstract

AbstractLanthanide nitrate complexes of diphosphazane dioxides Ph2P(O)N(Pri)P(O)Ph2 (1) and (PhO)2P(O)N(Me)P(O)(OPh)2 (2) have been synthesised and studied by conductometry, IR, multinuclear NMR spectroscopic methods and X‐ray diffraction. Ligand 2 is accessible by two different methods, viz., by direct oxidation of the phosp(III)azane ligand or by starting from phosph(V)azane chloro precursor. The structure of 2 is confirmed by X‐ray diffraction. Crystallographic data for 2: Triclinic, Space group P1, a = 10.078(1), b = 10.575(3), c = 12.364(4) Å, α = 75.70(2)°, α = 75.56(1)°, γ = 77.68(1)°, Z = 2, V = 1 220 Å3; structure refined to RF = 0.0459 on 3 495 data with F > 3σ(F). The diphosphazane dioxide ligand exhibits trans geometry in the solid state. The structure of a lanthanide complex, [Pr(NO3)3(2)2] (14) is also determined by X‐ray diffraction. Crystallographic data for 14: Trigonal, Space group P32, a = b = 15.710(2), c = 40.067(2) Å, Z = 6, V = 8 564 Å3; structure refined to RF = 0.0430 on 8 077 data with F > 5σ(F). The two diphosphazane dioxide ligands and the nitrate groups are coordinated to praseodymium in a bidentate chelate fashion. The geometry around the ten coordinated metal is distorted bicapped square antiprism.