Synthesis and characterization of oxomolybdenum(V) dinuclear complexes with b-alanine, L-serine and DL-isoleucine

摘要

New dinuclear molybdenum(V) complexes of the general formula [Mo_2O_4(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 [Mo_2O_3(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 [Mo_2O_4(acac)_2(β-alanine)]·H2O (1), [Mo_2O_4(acac)_2(L-serine)]·2C_2H_5OH·H_2O (2) and [Mo_2O_4(acac)_2(DL-isoleucine)] (3) were determined by single crystal X-ray diffraction. Powder diffraction data were analyzed for complexes [Mo_2O_4(acac)_2(β-alanine)] and [Mo_2O_4(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 {Mo_2O_4}~(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.