Synthesis and characterization of isatin complexes with M(CO)6, M=Cr or Mo

The reactions of [M(CO)6], M = Cr or Mo with isatin (isatH) were investigated. Three complexes with molecular formulae [Cr(CO)5(isatH)] (1), [Cr2O2(isatH)2] (2) and [Mo2O4(isatH)2] (3) were isolated from the reactions with isatH. In presence of bipyridine, bpy, two derivatives [Cr(CO)4(isatH)]·bpy (4) and [Mo(CO)4(isatH)]·bpy (5) were isolated. All complexes were characterized by elemental analysis, infrared, mass, ESR and 1H NMR spectroscopy. The UV–Vis spectra of the complexes in different solvents showed bands due to either metal-to-ligand or ligand-to-ligand charge transfer transition. Thermal properties of the complexes were investigated by TG technique.