Showing papers on "Carborane published in 1986"
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TL;DR: In this paper, ab initio calculations at the STO 3G level were performed on almost all of the possible isomers for the entire series of closo-carboranes, C2Bn−2Hn, 5 ⩽ n⩽ 12.
Abstract: Ab initio calculations at the STO‐3G level were performed on almost all of the possible isomers for the entire series of closo‐carboranes, C2Bn‐2Hn, 5 ⩽ n ⩽ 12. Geometry optimizations using the gradient method were also included in all calculations. We report here the relative energies obtained for the various isomers as well as the optimized structures. These calculations confirm our previous predictions of relative stabilities obtained from topological charge stabilization. Comparisons of our structures with those from experimental data provide us with a measure of reliability for bond distances obtained using ab initio SCF MO calculations at the STO‐3G level. Results from the geometry optimization substantiated the experimentally known fluxional behavior of the 8 and 11 atom polyhedra.
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TL;DR: On etudie, par des theories MO semiempirique et ab initio, les mecanismes possibles de la dimerisation du borirene en dihydro-1,4 diborinne- 1,4 and en son isomere plus stable tetracarba-2,3,4,5 nidohexaborane (6) as discussed by the authors.
Abstract: On etudie, par des theories MO semiempirique et ab initio, les mecanismes possibles de la dimerisation du borirene en dihydro-1,4 diborinne-1,4 et en son isomere plus stable tetracarba-2,3,4,5-nido-hexaborane (6)
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TL;DR: The silacarbaboranes (Me3Si)2C2B4H4]SiII(1) and SiIV(2) have been prepared and the structure of (2) has been determined by X-ray crystallography.
Abstract: The silacarbaboranes [(Me3Si)2C2B4H4]SiII(1) and [(Me3Si)2C2B4H4]2SiIV(2) have been prepared and the structure of (2) has been determined by X-ray crystallography.
22 citations
TL;DR: In this article, the coordination compounds of the type Pd(HPC) 2 - X 2, Pd (DPC)X 2 and Pd[NPC]X 2, where X Cl or Br and HPC = 1-diphenylphosphino- o -carborane; DPC =1,2-bis(diphensylphoshino)- o-carboranes; and NPC= 1-bis (dimethylamminophosphino, 2-diphosphino) - o
TL;DR: An efficient route leading to the isolation of nido -6-H 3 N-6-CB 9 H 11 and its reactions leading to other 6-L-6 CB 9H 11 species (L ǫ, Me 2 CNH or Me 2 S) was reported along with the formation of [2-L 1-C 5 H 5 -2,1-CCoB 9 H 9 ] closo -metallacarboranes as mentioned in this paper.
TL;DR: In this article, the coordination compounds of the type Pd(DMC)L and [Pd[PdS2P2]C where DMC behaves as a bidentate sulphur donor ligand and the tertiary phosphine (HPC) and ditertiary phosphines (DPC and NPC) are bonded through the phosphorous atoms to produce a planar PdS 2P2 skeleton of C2v symmetry.
Abstract: Coordination compounds of the type Pd(DMC)L and [Pd(DMC)2]C where DMC is 1,2-bis(mercapto)-o- carborane, L = 1-diphenylphosphino-o-carborane (HPC), 1,2-bis(diphenylphosphino-o-carborane (NPC) and C [dbnd] H+ or tetraethylammonium cation, have been prepared and characterized by IR, Raman and electronic spectroscopy, magnetic and conductivity measurements. DMC behaves as a bidentate sulphur donor ligand and the tertiary phosphine (HPC) and ditertiary phosphines (DPC and NPC) are bonded through the phosphorous atoms to produce a planar PdS2P2 skeleton of C2v symmetry.
TL;DR: Substitution of the 4,6-C2B7H13 cluster yields a series of 3-X-4,6,C2H7H12 derivatives whose 1H and 11B NMR spectra are reported and discussed.
TL;DR: The 11B nuclear quadrupole coupling in the title compounds was reported in this article, where the experimental technique applied was double resonance with level crossing, and the values for (e2qQ/h) 1+η2/3)1/2 are (in MHz, errors of last digits and assignments in brackets): o−carborane: 1.10(6) (B8,B10) (tentative), 1.22(6), 1−1,B12, 1.60(4) (b4,B
Abstract: The 11B nuclear quadrupole coupling in the title compounds is reported. The experimental technique applied was double resonance with level crossing. The values for (e2qQ/h)(1+η2/3)1/2 are (in MHz, errors of last digits and assignments in brackets): o‐carborane: 1.10(6) (B8,B10) (tentative), 1.22(6) (B9,B12), 1.60(4) (B4,B5,B7,B11), 1.86(4) (B3,B6); m‐carborane: 1.22(4) (B9,B10), 1.56(12) (all other borons, unresolved).
TL;DR: In this article, the reaction of carboranyl boron-centered radicals with phosphites occurs through the formation of a phosphoranyl radical, and the addition of the radicals derived from 2,6,7-tris(trichloromethyl)-3,5,8-trioxo-1,4-diphosphabicyclo[2.2] octane to 3,6-di-tert-butyl-ortho-benzoquinone was detected.
Abstract: 1.
The preparative photolysis of bis(m-carboran-9-yl)mercury and bis(p-carboran-2-yl)-mercury with trimethyl phosphite leads to the dimethyl esters of m- and p-B-carboranylphosphonic acids.
2.
The reaction of carboranyl boron-centered radicals with phosphites occurs through the formation of a phosphoranyl radical.
3.
The addition of the phosphoranyl radicals derived from 2,6,7-tris(trichloromethyl)-3,5,8-trioxo-1,4-diphosphabicyclo[2.2.2]octane to 3,6-di-tert-butyl-ortho-benzoquinone was detected. ESR spectroscopy was used to observe the tautomeric transfers of the phosphoranyl group between the ortho-benzoquinone oxygen atoms.
TL;DR: In this article, line splittings observed in the 10B and 11B NMR spectra of ortho-carborane d2 were used to derive the components of the boron quadrupole coupling tensors along the molecular dipole moment direction.
Abstract: Line splittings observed in the 10B and 11B NMR spectra of ortho‐carborane‐d2, when a solution of the compound is exposed to a very strong electric field, have been used to derive the components of the boron quadrupole coupling tensors along the molecular dipole moment direction. Furthermore, the magnitudes of the boron quadrupole coupling constants were measured from the spin‐lattice relaxation times (T1). The boron linewidths observed indicate the presence of a substantial scalar coupling contribution to T2 for both boron isotopes. The direction of the axis to be associated with the quadrupole coupling constant has been derived for some of the borons in o‐carborane by combing the EFNMR results with those of the T1 study.
TL;DR: In this article, carborane-containing poly(arylacetylenes) are obtained when poly(p-diethynylbenzene) with pendant ethynyl groups is reacted with decaborane in amidic solvents or in toluene in the presence of dimethylaniline.
Abstract: Macromolecular carborane-containing poly(arylacetylenes) are obtained when poly(p-diethynylbenzene) with pendant ethynyl groups is reacted with decaborane in amidic solvents or in toluene in the presence of dimethylaniline. The resulting carborane-containing polymers can be cured at 180 to 200°C to non-melting, insoluble products.