title: Synthesis and chemistry of the open-cage cobaltaheteroborane cluster [{(η(5)-C5Me5)Co}2B2H2Se2]: a combined experimental and theoretical study.
abstract: Reaction of [(η(5)-C5Me5)CoCl]2 with a two-fold excess of [LiBH4·thf] followed by heating with an excess of Se powder produces the dicobaltaselenaborane species [{(η(5)-C5Me5)Co}2B2H2Se2], , in good yield. The geometry of resembles a nido pentagonal [Co2B2Se2] bipyramid with a missing equatorial vertex. It can alternatively be seen as an open cage triple-decker cluster. Isolation of permits its reaction with [Fe2(CO)9] to give heterometallic diselenametallaborane [{(η(5)-C5Me5)Co}Fe(CO)3B2H2Se2], . The geometry of is similar to that of with one of the [(η(5)-C5Me5)Co] groups replaced by the isolobal, two-electron fragment [Fe(CO)3]. Both new compounds have been characterized by mass spectrometry, and by (1)H, (11)B and (13)C NMR spectroscopy. The structural architectures have been unequivocally established by crystallographic analysis. In addition, density functional theory calculations were performed to investigate the bonding and electronic properties. The large HOMO-LUMO gaps computed for both clusters are consistent with their thermodynamic stability. Natural bond order calculations predict the absence of metal-metal bonding interaction.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India. sghosh@iitm.ac.in.
authors.forename: Subrat Kumar
authors.initials: SK
authors.lastname: Barik
authors.forename: Vincent
authors.initials: V
authors.lastname: Dorcet
authors.forename: Thierry
authors.initials: T
authors.lastname: Roisnel
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Halet
authors.forename: Sundargopal
authors.initials: S
authors.lastname: Ghosh
mesh_terms: D003035:Cobalt / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004583:Electrons; D009682:Magnetic Resonance Spectroscopy; D008962:Models, Theoretical; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D011789:Quantum Theory; D013816:Thermodynamics
chemical_list: D009942:Organometallic Compounds; D003035:Cobalt