Coordination compounds of uranium with phosphorus donors

Dioxouranium(VI) adducts of the type UO2Cl2L or UO2Cl22L (L=l, l, l-tris(diphenylphenylphosphinomethyl) ethane ((C6H5)2PCH2)3(TDPPME); l, l, l-tris(di-phenylphosphino)methane((C6H5)2P)3CH(TDPPM), tris(2-cynoethyl)phosphine P(CH2CH2C≡N)3(TTCEP), triphenylphosphine (C6H5)3P(TPP), triphenylphosphine oxides (C6H5)3P=O(TPPO) have been obtained by the interaction of uranium(IV) chloride with the above mentioned ligands in tetrahydrofuran (THF) medium. Adducts obtained have been characterised on the basis of elemental analysis, molar conductance, magnetic moment and IR spectral (4000-200 cm-1) data. However, reaction of uranium(IV) chloride with TDPPME and TPPO in anhydrous and oxygen-free carbon tetrachloride (CCL4) gives green coloured compounds (UCl4(TDPPME)) and (UCl4(2TPPO)). Oxidation of U(IV) to dioxouranium(VI) in THF medium appears to be due to abstraction of oxygen from THF. (author). 1 tab., 12 refs