PROTON NUCLEAR MAGNETIC RESONANCE STUDIES OF 8-QUINOLINOL COMPLEXES OF THORIUM(4) AND URANIUM[6)

The proton nmr spectra of the 8-quinolinol (oxine, HOx) complexes of thorium(IV) and uranium(VI) in DMSO solutions have been recorded and analyzed. The data establish that the “solvated” complexes of thorium and uranium, ThOx4.HOx and UO2Ox2.HOx, only exist in the solid phase and dissociate to ThOx4 and UO2Ox2 in solution. The oxines in the latter complexes are equivalent on the basis of the nmr data. Studies of the UO2Ox3- complex also confirm that the three oxines are equivalent. Drying studies and differential thermograms of the various solvated oxine complexes of thorium and uranium have been used to characterize the solid species. The red form of UO2Ox2.HOx has a much greater thermal stability than the orange form and can be dried to constant weight at 150°. The maroon hydrate, UO2Ox2.3H2O, also is stable up to 150°. © 1969, American Chemical Society. All rights reserved.