Heterometallic cubane-type clusters were synthesized from the reaction of group 6 and 8 metallaboranes using transition-metal carbonyl compounds. Structural and spectroscopic study revealed the existence of novel "capped-cubane" geometry. In addition, the crystal structure of these clusters distinctly confirms the presence of boride unit as one of the vertices. These clusters possess 60 cluster valence electrons (cve) and six metal-metal bonds. A plausible pathway for the formation of ruthenium-capped cubane has been described. © 2012 IUPAC.

Sundargopal Ghosh

Department Of Chemistry

Boranes

Cluster compounds

Cubane

Heterometallics

METAL-METAL BONDS

Metallaboranes

Spectroscopic studies

VALENCE ELECTRON

Borides

Carbonylation

Chemical bonds

Iron

Molybdenum

ruthenium

selenium

Selenium compounds

Semiconducting selenium compounds

Spectroscopic analysis

Transition metals

Metallic compounds

Fulltext

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IIT Madras

Heterometallic cubane-type clusters containing group 13 and 16 elements*

Pure and Applied Chemistry

Thermolysis of diphenyl dichalcogenides, Ph2E2 (E = S, Se and Te) with an insitu generated intermediate, obtained from the reaction of [Cp*WCl4] (Cp* = η5-C5Me5) with [LiBH4·THF], yielded new tungstaheteroboranes, [(Cp*W)2(μ-EPh)(μ3-E)(μ-H)(B3H2EPh)], 1 and 2 (1: E = S; 2: E = Se), and [(Cp*W)2(μ-TePh)B5H5(μ-H)3], 4. Formation of compounds 1 and 2 substantiate the evidence of [(Cp*W)2B4H10], which supports our previous studies. Compound 4 has a capped octahedral geometry that is unique due to the presence of three W-H-B bridging hydrogens in a closo cluster. Alternatively, the shape of cluster 4 can be defined as oblatoarachno that can be derived from a heptagonal bipyramid. All the compounds have been characterized by mass spectrometry, 1H, 11B{1H}, IR and 13C{1H} NMR spectroscopy in solution and the structural architectures of 1 and 4 were unequivocally established by X-ray crystallographic analysis. The density functional theory calculations also yielded geometries in close agreement with the observed structures. © 2019 Elsevier B.V.

Journal of Organometallic Chemistry

Metallaheteroboranes containing group 16 elements: An experimental and theoretical study

Thermolysis of [Ru 3 (CO) 12 ] with an in-situ generated intermediate, obtained from the reaction of [Cp*MoCl 4 ] and [LiBH 4 .THF], led to the formation of [{Cp*Mo(CO) 2 }(μ 4 -B){Ru(CO) 3 } 3 (μ-H) 2 ], 2 and [{Cp*Mo(CO) 2 } 2 (μ 4 -B){Ru(CO) 3 } 2 (μ-H)], 3 (Cp* = η 5 -C 5 Me 5 ). In a similar fashion, when [Ru 3 (CO) 12 ] was thermalized with [(Cp*Rh) 2 B 2 H 6 ], obtained from a fast metathesis reaction of [Cp*RhCl 2 ] 2 , 4 and [LiBH 4 .THF], yielded a novel heterometallic boride cluster [(Cp*Rh)(μ 6 -B){Ru(CO) 3 } 4 {RuH(CO) 2 }], 5. Both compounds 2 and 3 can be described as 50-cluster valence electron (cve) hetero-metallic boride clusters, in which the boron atom is in semi-interstitial position of a M 4 -butterfly geometry. Compound 5 contains 86 cluster valence-electrons, in which the boron atom is inside of an octahedral hole composed of one rhodium and five ruthenium atoms. Computational studies on the ground of density functional theory has been undertaken to analyze the bonding of 2, 3 and 5. The structural optimization yields geometries in agreement with the structure determinations and computed 11 B chemical shifts accurately reflect the observed shifts. The molecular orbital analysis of them shows that all the valence orbitals of boron have been participated in bonding and therefore provides the “encapsulation” picture of the boron atom. All the compounds have been characterized by IR and 1 H, 11 B, and 13 C NMR spectroscopy, and the geometries of the structures were unequivocally established by crystallographic analyses of compounds 2, 3 and 5. © 2016

Heterometallic boride clusters of group 6 and 9 transition metals

The reaction of [(Cp*Ta)2B4H 9(μ-BH4)] (1; Cp* = η5-C5Me5) with [Fe2(CO) 9] in hexane yielded [(Cp*Ta)2B 5H7{Fe(CO)3}2] (2) and [(Cp *Ta)2B5H9{Fe(CO) 3}4](3) in moderate yield. Cluster 2 represents the first example of a bicapped pentagonalbipyramidal metallaborane with a deformed equatorial plane, and 3 can be described as a fused cluster in which two pentagonalbipyramidal units are fused through a common 3-vertex triangular face. Compounds 2 and 3 have been characterized by mass spectrometry and IR, 1H, 11B, and 13C NMR spectroscopy, and the geometric structures were unequivocally established by crystallographic analysis. © 2011 American Chemical Society.

Inorganic Chemistry

Condensed tantalaborane clusters: Synthesis and structures of [(Cp *Ta)2B5H7{Fe(CO) 3}2] and [(Cp*Ta)2B 5H9{Fe(CO)3}4]

Metal-rich metallaboranes: An exo-Fe(CO)3 moiety linked to a cubane core is the most prominent feature of complexes [(Cp*M) 2(μ3-E)2B2H(μ-H){Fe(CO) 2}2Fe(CO)3] (M=Mo, E=S, Se; M=Ru, E=CO; Cp*=n5-C5Me5), which are the first heterobimetallic cubane-type clusters with a boride unit (see structure). © 2011 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim.

Angewandte Chemie - International Edition

A family of heterometallic cubane-type clusters with an exo-Fe(CO) 3 fragment anchored to the cubane

Reaction of [(η5-C5Me5)MCl4], 1-2 (1: M = Mo and 2: W) with six fold excess of [LiBH4·thf] followed by thermolysis with excess chalcogen powders (S, Se and Te) yielded dichalcomolybda- and tungstaboranes, [(η5-C5Me5M)2B4H4E2], 5-8 (5: M = Mo, E = S; 6: M = Mo, E = Se; 7: M = Mo, E = Te; 8: M = W, E = Se) in modest yields. The geometry of 5-8 resembles a hexagonal bipyramid with a missing connectivity of two chalcogen vertices and a very short cross cage metal-metal bonding. All these new dichalcometallaboranes have been characterized by mass, 1H, 11B, 13C NMR spectroscopy, and the structural types were unequivocally established by crystallographic analysis of compound 6. © 2009 Elsevier B.V. All rights reserved.

Direct insertion of sulfur, selenium and tellurium atoms into metallaborane cages using chalcogen powders

Reaction of [CpMoCl4], 1 (Cp* = η5-C 5Me5), with [LiBH4 thf] in toluene at -70 °C, followed by pyrolysis with excess dichalcogenides RE-ER (R = Ph, CH 2Ph, 2,6-(tBu)2-C6H2OH, (CH3)3C = tBu); E = S, Se) yielded a new class of hybrid clusters, 3-8: (3, [(CpMo)2(μ-η1-SPh) 2(μ3-S)(H2BSPh)]; 4, [(CpMo) 2B5H8(SPh)]; 5, [(CpMo)2B 5H8(SePh)]; 6, [(CpMo)2B2S 2H2(μ-η1-S)]; 7, [(CpMo) 2B2H5(BSR)2(μ-η1- SR)], (R = 2,6-(tBu)2-C6H2OH); and 8, [(CpMo)2B2H5(BSePh)2(μ- η1-SePh)]. Compounds 3-8 have been isolated in modest yields as green or brown crystalline solids. In parallel with 3-8, [(CpMo) 2B5H9] was isolated as a major product in all cases. The isolation and structural characterization of compounds 3 and 6-8 provided the first direct evidence of the existence of [(CpMo)2B 4H8], 2, an intermediate in the formation of [(CpMo) 2B5H9]. These new compounds have been characterized in solution by mass spectrometry, 1H, 11B, 13C NMR, and IR spectroscopy, and elemental analysis. The structural types were unequivocally established by X-ray crystallographic analysis of compounds 3-8. © 2010 American Chemical Society.

Chemistry of molybdaboranes: Synthesis, structures, and characterization of a new class of open-cage dimolybdaheteroborane clusters

Organometallics

Half-Sandwich Group 8 Borylene Complexes: Synthetic and Structural Studies and Oxygen Atom Abstraction Chemistry

Heterometallic cubane-type clusters containing group 13 and 16 elements

Journal	Pure and Applied Chemistry
ISSN	00334545
Open Access	Yes