Synthesis and Crystal Structures of Two Novel Molybdenum(V) Complexes with Glycine and D,L-Valine

Marina Tašner,^a Biserka Prugovečki,^a Draginja Mrvoš-Sermek,^a Branka Korpar-Čolig,^a Gerald Giester^b and Dubravka Matković-Čalogović^a,*

^a Laboratory of General and Inorganic Chemistry , Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000 Zagreb
^b Institute for Mineralogy and Crystallography, University of Vienna, Althanstr. 14, A-1090 Vienna, Austria
* Corresponding author: E-mail: dubravka@chem.pmf.hr

Abstract
Two novel molybdenum(V) complexes, [Mo₂O₄(acac)₂(gly)](EtOH)(H₂O), 1, and [Mo₂O₄(acac)₂(D,L-val)], 2, (acac = acetylacetonato, EtOH = ethanol), were synthesized by the reaction of [Mo₂O₃(acac)₄] and amino acids glycine and D,Lvaline, respectively. The complexes were characterized by elemental and IR spectral analysis. Their structures were determined by the single crystal X-ray diffraction method. Both complexes are dinuclear, with singly bonded Mo—Mo in the {Mo₂O₄}²⁺ core, a carboxylato bridging amino acid, and with each Mo atom additionally coordinated by a bidentate acetylacetonato ligand. Crystal data: C₁₄H₂₇Mo₂NO₁₂ (1) crystallizes in the monoclinic system, space group P2₁/n, with a = 8.439(2), b = 20.613(4), c = 12.639(3) Å, β= 98.410(10)°, Z = 4; C₁₅H₂₅Mo₂NO₁₀ (2) crystallizes in the orthorhombic system, space group Pbca with a = 13.596(1), b = 19.346(1), c = 15.080(1) Å, Z = 8.

Keywords: Molybdenum(V) complexes; crystal structure; amino acid complexes