Synthesis and characterization of oxomolybdenum(V) dinuclear complexes with β-alanine, l-serine and dl-isoleucine

Abstract

New dinuclear molybdenum(V) complexes of the general formula [Mo2O4(acac)2aa], where acac=acetylacetonato, aa=amino acid: β-alanine, l-serine or dl-isoleucine were obtained by the reaction of the dinuclear oxomolybdenum complex [Mo2O3(acac)4] with an amino acid in ethanol. Complexes were characterized by vibrational spectroscopy (IR, Raman) and thermal methods (TG/DSC). The crystal and molecular structures of [Mo2O4(acac)2(β-alanine)]·H2O (1), [Mo2O4(acac)2(l-serine)]·2C2H5OH·H2O (2) and [Mo2O4(acac)2(dl-isoleucine)] (3) were determined by single crystal X-ray diffraction. Powder diffraction data were analyzed for complexes [Mo2O4(acac)2(β-alanine)] and [Mo2O4(acac)2(l-serine)] whose single-crystal data were those of the solvates 1 and 2. The obtained complexes 1–3 are dinuclear with the {Mo2O4}2+ core. The crystal structures showed that the molybdenum atoms are octahedrally coordinated with one terminal oxo-oxygen, two bridging oxo-oxygen atoms, two oxygen atoms from the bidentate acetylacetonato ligand and one oxygen atom from the bridging carboxylato group of the corresponding amino acid. A common feature of all three complexes is formation of tubular 2D layers in 2 and puckered 2D layers in 1 and 3.