Synthesis, characterization and crystal structure of a binuclear molybdenum(VI) oxo complex of a dianionic tetradentate Schiff-base ligand

Abstract

Reaction in methanol solution of [NBu₄]₄[Mo₈O₂₆] with 1,3,5,7-tetraazatricyclo[3.3.1.1^3.7]decane (hexamethylenetetramine, hmt) and salicylaldehyde yielded the complex [Hhmt][Mo₂O₄(µ-O)(µ-OMe)(o-OC₆H₄CHNCH₂NCHC₆H₄O-o)] which has been characterized by elemental analysis, IR and ¹H NMR spectroscopy. A single-crystal analysis revealed that the complex possesses the usual Mo₂O₅²⁺ core and that the Schiff-base ligand complexes in a tetradentate manner through the atoms ONON, acts forming two six-membered rings. The two Mo atoms are bridged by a methoxo group, giving each a distorted-octahedral configuration.