Synthesis and reactions of uranium(IV) tetrathiolate complexes

Uranium(IV) tetrathiolate complexes were made by (a) reaction of U(NEt2)4 with RSH (R = Et, Pri, Bun or But), (b) treatment of U(BH4)4 with RSH (R = Bun or Ph) or of U(SBun)4 with PhSH or (c) oxidation of uranium metal by RSSR (R = Et, Pri or Ph). Rearrangement of [U(SBut)4(py)3](py = pyridine) in toluene gave the trinuclear cluster [U3S(SBut)10] with liberation of ButSH and Me2CCH2. Reaction of U(SPri)4 with [NEt3H][BPh4] in the presence of hexamethylphosphoric triamide (hmpa) afforded the cationic compound [U(SPri)2(hmpa)4][BPh4]2 which presents a trans-octahedral crystal structure. Iodinolysis of U(SPri)4 in pyridine led to the formation of [U(SPri)2l2(py)3] which adopts a pentagonal-bipyramidal configuration in its crystalline form. The trithiocarbonate (PriS)2CS was obtained by reaction of U(SPri)4 with CS2.