SYNTHESIS, IR AND X-RAY STUDIES OF A DIOXOURANIUM(VI) NITRATE COMPLEXWITH N,N'-TETRAETHYL-N''-TRICHLORACETYLPHOSPHORTRIAMIDE

A new dioxouranium(VI) nitrate complex with N,N'-tetraethyl-N ''-trich loracetylphosphortriamide (HL = CCl3C(O)N(H)P(O)(NEt2)(2)) of composit ion UO2(HL)(2)(NO3)(2) (1) has been synthesised. The IR spectroscopic data reveal that the ambidentate ligand is coordinated to the metal ce nter in a monodentate manner via the phosphoryl oxygen atom. The cryst al and molecular structure of 1 has been determined from X-ray diffrac tion data (triclinic, space group <P(1)over bar> with a = 9.225(2), b = 10.360(2), c = 12.249(2) Angstrom, alpha = 100.02(1), beta = 103.81( 1), gamma = 108.80 (1)degrees, Z = 1; R = 0.037 for 4092 unique reflec tions. The structure is made up of centrosymmetric molecules in which the neutral ligands HL are monocoordinated. Phosphoryl and carbonyl gr oups of the HL moieties are in the trans positions to each Ether. The axial vertices of the distorted hexagonal bipyramid of uranium are occ upied by two oxo ligands [U-O 1.753(5) Angstrom] while six oxygen atom s of phosphoryl and nitrate groups lie in the equatorial plane [U-O 2. 347(5)-2.547(6) Angstrom].