title: Cubane-type Mo3FeS4(4+,5+) complexes containing outer diphosphane ligands: ligand substitution reactions, spectroscopic studies, and electronic structure.
abstract: A general protocol to access Mo(3)FeS(4)(4+) clusters selectively modified at the Fe coordination site is presented starting from the all-chlorine Mo(3)(FeCl)S(4)(dmpe)(3)Cl(3) (1) [dmpe = 1,2-bis(dimethylphosphane-ethane)] cluster and tetrabutylammonium salts (n-Bu(4)NX) (X = CN(-), N(3)(-), and PhS(-)). Clusters Mo(3)(FeX)S(4)(dmpe)(3)Cl(3) [X = CN(-) (2), N(3)(-) (3), and PhS(-) (4)] are prepared in high yield, and comparison of geometric and redox features upon modification of the coordination environment at the Fe site at parity of ligands at the Mo sites is also presented. The existence of the cubane-type Mo(3)FeS(4)(4+,5+) redox couple is demonstrated by cyclic voltammetry and for compound 1 by cluster synthesis and X-ray structure determinations. Ground states for the 1/1(+) redox couple are evaluated on the basis of magnetic susceptibility measurements, electron paramagnetic resonance, and (57)Fe Mössbauer spectroscopy aimed at providing an input of experimental data for electronic structure determination based on density functional theory calculations.
authors.affiliation: Departament de Química Física i Analítica, Universitat Jaume I, Av. Sos Baynat s/n, E- 12071 Castelló, Spain.
authors.forename: Ivan
authors.initials: I
authors.lastname: Sorribes
authors.forename: Francesc
authors.initials: F
authors.lastname: Lloret
authors.forename: Joao C
authors.initials: JC
authors.lastname: Waerenborgh
authors.forename: Victor
authors.initials: V
authors.lastname: Polo
authors.forename: Rosa
authors.initials: R
authors.lastname: Llusar
authors.forename: Cristian
authors.initials: C
authors.lastname: Vicent
mesh_terms: D004583:Electrons; D007501:Iron / Q000737:chemistry*; D008024:Ligands; D060328:Magnetic Phenomena; D008958:Models, Molecular; D008968:Molecular Conformation; D008982:Molybdenum / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D010720:Phosphines / Q000737:chemistry*; D011789:Quantum Theory; D013057:Spectrum Analysis; D013455:Sulfur / Q000737:chemistry*
chemical_list: D008024:Ligands; D009942:Organometallic Compounds; D010720:Phosphines; D013455:Sulfur; D008982:Molybdenum; D007501:Iron; C044646:phosphine