PREPARATION OF MONO-PENTAMETHYLCYCLOPENTADIENYL URANIUM(IV) SULFIDO CLUSTERS THROUGH OXIDATION OF (ETA-C(5)ME(5))UL(2)(THF)(3) - X-RAY STRUCTURAL CHARACTERIZATION OF -C(5)ME(5))(3)U-3(MU(3)-I)(MU(3)-S)(MU(2)-I)(3)I-3

Reaction of the mono-cyclopentadienyl uranium(III) complex (eta-C(5)Me (5))UI2(THF)(3) (1) with one or two equivalents of carbon disulfide in toluene solution produces [(eta-C(5)Me(5))UI2(THF)(3)]S-2 (2) in 60-8 0% yield. Compound 2 is converted to the trimetallic uranium(IV) clust er -C(5)Me(5))(3)U-3(mu(3)-S)(mu(3)-I)(mu(2)-I)(3)I-3 (3) in low yield upon standing in solution over a period of weeks. The solid state str ucture of 3 was determined, and if the eta-C(5)Me(5) ligand is conside red to occupy a single coordination site, then the molecular structure of 3 can be viewed as a member of the well-known M(3)(mu(3)-X)(2)(mu( 2)-X)(3)X(6) structural type, with triply bridging sulfide and iodide ligands capping the triangular faces of the cluster, U-I, U-mu(2)-I, a nd U-mu(3)-I bond lengths average 2.952(5), 3.096(8), and 3.294(5) Ang strom, respectively, while U-mu(3)-S bond lengths average 2.75(2) Angs trom. Crystal data for 3 (at -171 degrees C): Monoclinic space group P 2(1)/n, a=12.224(4), b = 17.098(6), c = 21.631(6) Angstrom, beta = 90. 71(1)degrees, V = 4520.82 Angstrom(3), d(calc) = 2.998 g cm(-3), Z = 4 , R = 0.089, R(w)= 0.083.