949494-47-7Relevant articles and documents
Chemistry of molybdenum with hard-soft donor ligands. 2. Molybdenum(VI), -(V), and -(IV) oxo complexes with tridentate schiff base ligands
Purohit, Sanchita,Koley, Aditya P.,Prasad, Lakkaraju S.,Manoharan,Ghosh, Saktiprosad
, p. 3735 - 3742 (2008/10/08)
The synthesis and characterization of a number of oxomolybdenum(VI), -(V), and -(IV) complexes with salicylaldehyde thiosemicarbazones as the SNO-donor metal-binding substrates are described. The Mo(VI) complexes are cis-dioxo, MoO2(SNO), with one coordination site available for substrate binding. The Mo(V)-oxo complexes are of the type MoO(SNO)X2 (X = Cl, Br) with a distorted-octahedral geometry. The Mo(IV)-oxo complexes, MoO(SNO), are derived from the corresponding Mo(VI)-dioxo complexes by oxo abstraction with PPh3. The cyclic voltammograms for MoO2(SNO) complexes are typically irreversible, involving Mo(VI)/Mo(V) and Mo(V)/Mo(IV) reductive responses. The Mo(V)-oxo complexes display unique voltammograms exhibiting Mo(V)/Mo(IV), Mo(IV)/Mo(III), and Mo(V)/Mo(VI) couples. The Mo(IV)-oxo complexes are oxidized to Mo(V)-oxo complexes and undergo one-electron reduction to the corresponding Mo(III) species. EPR results indicate that the isotropic metal hyperfine coupling constant of Mo(V)-oxo complexes decreases with an increase of covalent character in going from chlorine to their bromine analogues. The spin-orbit coupling of bromide ligands appears to be the dominant factor contributing to the drastic change in isotropic g values.
