Binuclear complexes of rhodium (I) bridged by 1,2-dicarba-closo-dodecaborane-1,2-dichalcogenolato ligands: molecular structures of the complexes [Rh2(COD)2(μ2-E2C2(B10H10))] [E = S, Se] and [Rh2(CO)4(μ2-S2C2(B10H10))]

Four new dichalcogenolate carborane bridged binuclear rhodium(I) complexes [Rh2(COD)2(μ2-E2C2(B10H10))] [COD = cycloocta-1,5-diene (C8H12), E = S (2a), Se (2b)] and [Rh2(CO)2(μ2-E2C2(B10H10))] [E = S (3a), Se (3b)] have been prepared by the reactions of the dilithium dichalcogenolate carboranes Li2E2C2B10H10 (E = S, Se) with [Rh(COD)Cl]2 or [Rh(CO)2Cl]2, respectively. The complexes have been fully characterized by 1H, 13C, 11B NMR and IR spectroscopy as well as by element analyses. The molecular structures of 2a, 2b and 3a have been determined by single-crystal X-ray diffraction analyses, which show the strong metal–metal interaction between two rhodium atoms.