title: Synthesis and structure of singly bridged and doubly bridged [MoFe(3)S(4)] double cubanes with bidentate phosphine ligands.
abstract: The reactions of the (Et(4)N)(2)[(Cl(4)-cat)(MeCN)MoFe(3)S(4)Cl(3)] (I) cluster with Fe(pp)(2)Cl(2) (pp = depe (bis(1,2-diethylphosphino)ethane) or dmpe (bis(1,2-dimethylphosphino)ethane)) produced the [(Cl(4)-cat)MoFe(3)S(4)(pp)(2)Cl](2)(mu-pp) (pp = depe (III) or dmpe (V)) singly bridged double cubanes. The reactions of I with the same bidentate phosphine ligands in the presence of NaBPh(4) also produced III and the [(Cl(4)-cat)MoFe(3)S(4)(dmpe)(2)](2)(mu-S)(mu-dmpe) (VI) doubly bridged double cubane, respectively. The byproduct (BPh(4))[Fe(dmpe)(2)(MeCN)Cl] (VII) has been isolated from the reaction mixture and crystallographically characterized. The depe analogue of VI, [(Cl(4)-cat)MoFe(3)S(4)(depe)(2)](2)(mu-S)(mu-depe) (IV), has been successfully prepared from III in the presence of excess Li(2)S. Similar reactions with (Et(4)N)(2)[Fe(4)S(4)(SPh)(4)] (VIII) have resulted in the formation of the neutral Fe(4)S(4)(depe)(2)(SPh)(2) (IX) cluster. The chloride analogue of IX, Fe(4)S(4)(depe)(2)Cl(2) (XI), has been obtained by a reaction of IX with benzoyl chloride. The crystal and molecular structures of III, VI, VII, and XI have been determined by single-crystal X-ray crystallography. The electrochemical and spectroscopic properties, including the Mossbauer spectra of the new clusters, have been determined and analyzed.
authors: The Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, USA.
authors: Jaehong
authors: J
authors: Han
authors: Dimitri
authors: D
authors: Coucouvanis
mesh_terms: D001952:Bridged-Ring Compounds / Q000138:chemical synthesis / Q000737:chemistry; D002625:Chemistry, Organic / Q000379:methods*; D018360:Crystallography, X-Ray; D004578:Electron Spin Resonance Spectroscopy; D007501:Iron / Q000737:chemistry; D008024:Ligands; D008968:Molecular Conformation; D008982:Molybdenum / Q000737:chemistry; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D015204:Spectroscopy, Mossbauer; D013057:Spectrum Analysis; D013455:Sulfur / Q000737:chemistry
chemical_list: D001952:Bridged-Ring Compounds; D008024:Ligands; D009942:Organometallic Compounds; D013455:Sulfur; D008982:Molybdenum; D007501:Iron