The First Example of a Seven-Coordinate Vanadium(III) Thiolate Complex Containing the Hydrazine Molecule, an Intermediate of Nitrogen Fixation

The first example of a seven-coordinate vanadium(III) thiolate complex, [V(PS3″)(N₂H₄)₃] (1), where PS3″ = [P(C₆H₃-3-Me₃Si-2-S)₃] ^3-, has been synthesized and characterized. Compound 1 contains a tetradentate ligand (PS3″) and three hydrazine molecules, forming a capped octahedral geometry. A five-coordinate vanadium(III) complex, [V(PS3)(1-Me-Im) (2), where PS3 = [P(C₆H₄-2-S) ₃]^3- and 1-Me-Im = 1-methyl-imidazole was also obtained. Compound 2 adopts a trigonal bipyramidal geometry, in which the vanadium is ligated by the title ligand, PS3, and one 1-Me-Im molecule.