UC Santa Barbara

Reaction of 4 equiv. of [Li(TMEDA)]2[1,2-S2C6H4] with [ThCl4(DME)2] or [UCl4(THF)3] in THF results in formation of [Li(THF)2]4[An(1,2-S2C6H4)4] (An = Th, 1; An = U, 2), whereas reaction of 4 equiv. of [Li(TMEDA)]2[1,2-S2C6H4] with UCl4 in Et2O results in formation of [Li(TMEDA)]4[U(1,2-S2C6H4)4] (3). Complexes 1–3 represent the first reported benzenedithiolate complexes of the actinides. They were characterized by NMR spectroscopy and X-ray crystallography. In the solid state, complexes 1–3 exhibit triangular dodecahedral geometries about their actinide centers. Additionally, their Li+ cations are bound by two sulfur atoms of adjacent [1,2-S2C6H4]2− ligands, in addition to two solvent donor atoms. In solution, complexes 2 and 3 exhibit spectral data consistent with S 4 symmetry (and non-exchanging Li+ sites), whereas complex 1 exhibits spectral properties consistent with labile Li+ cations.