Two mononuclear molybdenum(VI) oxo complexes with tridentate hydrazone ligands: Synthesis and crystal structures

Reaction of [MoO 2 (Acac) 2 ] (Acac = acetylacetonate) with two similar hydrazone ligands in methanol yielded two mononuclear molybdenum(VI) oxocomplexes with general formula [MoO 2 (L)(CH 3 OH)], where L = L 1 = (4-nitrophenoxy)acetic acid [1-(3-ethoxy-2-hydroxyphenyl)methylidene]hydrazide (H 2 L 1 ) and L = L 2 = (4-nitrophenoxy)acetic acid [1-(5-bromo-2-hydroxyphenyl)methylidene]hydrazide (H 2 L 2 ). Crystal and molecular structures of the complexes were determined by single crystal X-ray diffraction method. All investigated compounds were further characterized by elemental analysis and FT-IR spectra. Single crystal X-ray structural studies indicate that the hydrazone ligands coordinate to the MoO 2 cores through enolate oxygen, phenolate oxygen, and azomethine nitrogen. The Mo atoms in both complexes are in octahedral coordination.