title: Oxo-molybdenum(VI,V,IV) complexes of the facially coordinating tris(mercaptoimidazolyl)borate ligand: synthesis, characterization, and oxygen atom transfer reactivity.
abstract: A series of monooxo-Mo(IV,V) and dioxo-Mo(VI) complexes of the "soft" tripodal ligand, sodium tris(mercaptoimidazolyl)borate (NaTm(Me)), have been synthesized as potential oxygen atom transfer (OAT) models for sulfite oxidase. Complexes have been characterized by X-ray crystallography, cyclic voltammetry, and EPR, where appropriate. Oxygen atom transfer kinetics of Tm(Me)MoO(2)Cl, both stoichiometric and catalytic, have been studied by a combination of UV-vis and (31)P NMR spectroscopies under a variety of conditions. OAT rates are consistent with previously established relationships between redox potential/reactivity and mechanistic studies. The analysis of these complexes as potential structural and functional analogues of relevance to molybdoenzymes is further discussed.
authors.affiliation: Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182-1030, USA.
authors.forename: Ba L
authors.initials: BL
authors.lastname: Tran
authors.forename: Carl J
authors.initials: CJ
authors.lastname: Carrano
mesh_terms: D001881:Borates / Q000737:chemistry*; D018360:Crystallography, X-Ray; D007700:Kinetics; D008024:Ligands; D008958:Models, Molecular; D008982:Molybdenum / Q000737:chemistry*; D009942:Organometallic Compounds / Q000138:chemical synthesis*; D010100:Oxygen / Q000737:chemistry*; D013057:Spectrum Analysis; D050876:Sulfite Oxidase / Q000737:chemistry*
chemical_list: D001881:Borates; D008024:Ligands; D009942:Organometallic Compounds; C044659:molybdate; D008982:Molybdenum; D050876:Sulfite Oxidase; D010100:Oxygen