Synthesis and characterization of half-sandwich iridium(III) and rhodium(III) complexes bearing organochalcogen ligands

Reactions of [Cp∗M(μ-Cl)Cl]2 (M = Ir, Rh; Cp∗ = η5-pentamethylcyclopentadienyl) with bi- or tri-dentate organochalcogen ligands Mbit (L1), Mbpit (L2), Mbbit (L3) and [TmMe]− (L4) (Mbit = 1,1′-methylenebis(3-methyl-imidazole-2-thione); Mbpit = 1,1′-methylene bis (3-iso-propyl-imidazole-2-thione), Mbbit = 1,1′-methylene bis (3-tert-butyl-imidazole-2-thione)) and [TmMe]− (TmMe = tris (2-mercapto-1-methylimidazolyl) borate) result in the formation of the 18-electron half-sandwich complexes [Cp∗M(Mbit)Cl]Cl (M = Ir, 1a; M = Rh, 1b), [Cp∗M(Mbpit)Cl]Cl (M = Ir, 2a; M = Rh, 2b), [Cp∗M(Mbbit)Cl]Cl (M = Ir, 3a; M = Rh, 3b) and [Cp∗M(TmMe)]Cl (M = Ir, 4a; M = Rh, 4b), respectively. All complexes have been characterized by elemental analysis, NMR and IR spectra. The molecular structures of 1a, 2b and 4a have been determined by X-ray crystallography.