17702-35-1Relevant articles and documents
Quantitative Assessment of Substitution NMR Effects in the Model Series of o-Carborane Derivatives: α-Shift Correlation Method
?tíbr, Bohumil,Tok, Oleg L.,Holub, Josef
, p. 8334 - 8340 (2017)
The principles of a new α-shift correlation (ASC) NMR method are demonstrated on a model series of substituted derivatives of o-carborane for which reliable NMR data are available. This graphical method revealed an acceptable linear correlation between α(11B) or α(13C) shifts and those induced by substituents in unsubstituted (u) positions of the carborane cluster. The linearity holds for all nuclei involved in skeletal bonding: Δδ(N)u = g × α (where N = 11B, 13C, and 1H). The factor g (slope of the correlation line × 102) becomes an important measure of sensitivity of a given cage position to substituent changes. The β, γ, and δ = A (= antipodal) shifts can be therefore derived from the α-shift, are linearly proportional, and reflect additive character in double substitution. The ASC method appears to be an important tool for quantitative assessment of substituent NMR effects in all exo-substituted boron-cluster systems.
Dicarba-closo-dodecaboranes with one and two ethynyl groups bonded to boron
Himmelspach, Alexander,Finze, Maik
, p. 2012 - 2024 (2010)
The diethynyldicarba-closo-dodecaboranes 1,2-R2-9,12(HCC) 2-ClOSO-1,2-C2B10H8 [R = H (1a), Me (2a)j and 9,10(HCC)2-closo-1,7-C2B10H 10 (3a) were obtained by
Synthesis and deborination of polyhalo-substituted ortho-carboranes
Rudakov,Kurman,Potkin
, p. 1137 - 1142 (2011)
Tetraiodo-1,2-dicarba-closo-dodecaborane and 9-bromo-8,10,12-triiodo-1,2- dicarba-closo-dodecaborane were synthesized by oxidative iodination of 1,2-dicarba-closo-dodecaborane and 9-bromo-1,2-dicarba-closododecaborane, respectively, in AcOH using a mixture of nitric and sulfuric acid as an oxidant of iodine. The intermediates in the ortho-carborane iodination were identified. By the action of elemental bromine on 9-iodo- 1,2-dicarba-closo-dodecaborane in the presence of aluminum chloride catalyst 9-iodo-8,10,12-tribromo-1,2- dicarba-closo-dodecaborane was obtained. Deborination of the synthesized substances with an alcohol solution of KOH led to formation of 1,5,6,10-tetraiodo-5-bromo-1,6,10-triiodo- and 5-iodo-1,6,10-tribromo-7,8- dicarbaundecaborates methylammonium salts. Pleiades Publishing, Ltd., 2011.
Luminescent metal complexes featuring photophysically innocent boron cluster ligands
Kirlikovali, Kent O.,Axtell, Jonathan C.,Gonzalez, Alejandra,Phung, Alice C.,Khan, Saeed I.,Spokoyny, Alexander M.
, p. 5132 - 5138 (2016)
We report the synthesis and characterization of a series of d8 metal complexes featuring robust and photophysically innocent strong-field chelating 1,1′-bis(o-carborane) (bc) ligand frameworks. A combination of UV-Vis spectroscopy, single crystal X-ray structural analysis, and DFT calculations of these species suggest that the dianionic bc ligand does not contribute to any visible metal-to-ligand charge transfer (MLCT) transitions, yet it provides a strong ligand field in these complexes. Furthermore, a bc-based Pt(ii) complex containing a 4,4′-di-tert-butyl-2,2′-bipyridine ligand (dtb-bpy) has been prepared and was found to display blue phosphorescent emission dominated by MLCT from the Pt(ii) center to the dtb-bpy ligand. Importantly, the bulky three-dimensional nature of the bc ligand precludes intermolecular Pt(ii)?Pt(ii) interactions in the solid state where the resulting compounds retain their emission properties. This study opens a potentially new avenue for designing organic light-emitting diode (OLED) materials with tunable properties featuring photophysically innocent boron-rich cluster ligands.
9,12-diiodo-1,2-dicarba-closo-dodecaborane(12)
Batsanov, Andrei S.,Fox, Mark A.,Howard, Judith A.K.,Hughes, Andrew K.,Johnson, Andrew L.,Martindale, Steven J.
, p. o74-o76 (2003)
The title compound, C2H10B10I2, has a pseudo-icosahedral cluster geometry. The crystal structure features an intermolecular C-H...I-B hydrogen bond with a normalized H...I distance of 3.00 A.
Synthesis and structural characterization of group 10 metal-carboryne complexes
Qiu, Zaozao,Deng, Liang,Chan, Hoi-Shan,Xie, Zuowei
, p. 4541 - 4547 (2010/12/20)
A series of group 10 metal-carboryne complexes were prepared from an equimolar reaction of MCl2(PR3)2 with Li 2C2B10H10-nXn (M = Ni, Pd, Pt; X = Br, I, Ph; n = 0, 1, 2). They were fully characterized by various spectroscopic techniques, elemental analyses, and X-ray diffraction studies. These complexes have similar solid-state structures, in which the metal atom is bonded to two cage carbon atoms and coordinated to two phosphorus atoms in a planar geometry. The coordinated phosphines are labile and can be replaced by other Lewis bases. The bonding interactions between the metal and the carboryne unit can be described as a resonance hybrid of both the M-C σ- and M-C π-bonding forms. These complexes can be viewed as 16e species.
Designed synthesis of new ortho-carborane derivatives: From mono- to polysubstituted frameworks
Barbera, Gemma,Vaca, Albert,Teixidor, Francesc,Sillanpaeae, Reijo,Kivekaes, Raikko,Vinas, Clara
, p. 7309 - 7316 (2009/02/06)
The use of nucleophilic and electrophilic processes allow the designed synthesis of several B-iodinated derivatives of o-carborane. Because of the straightforward Pd-catalyzed conversion of B-I to B-C bond with Grignard reagents, such as methylMgBr and biPhenylMgBr, both, symmetrical 3,6-R 2-1,2-closo-C2B10H10 and asymmetrical 3-I-6-Me-1,2-closo-C2B10H10 could be obtained. Not only conventional reactions in solution have been studied but also a highly efficient, clean and fast solvent-free procedure has provided successful results to regioselectively produce B-iodinated o-carborane derivatives by a careful control of the reaction conditions. The high number of nonequivalent leaving groups in boron iodinated o-carborane derivatives opens the possibility through B-C coupling to materials with novel possibilities and to self-assembling due to the enhanced polarizability of the C-H bond.
A solvent-free regioselective iodination route of ortho-carboranes
Vaca, Albert,Teixidor, Francesc,Kivekaes, Raikko,Sillanpaeae, Reijo,Vinas, Clara
, p. 4884 - 4885 (2007/10/03)
Tetraiodo-ortho-Carborane based x-ray contrast agents was prepared n a high yield, fast, clean, regioselective fashion by a solvent-free reaction of ortho-carboranes with iodine in sealed tubes. ortho-Carborane and its derivatives can be iodinated under electrophilic conditions using Lewis or Bronsted acid catalysts. The Pyrex tube was opened and gaseous HI removed by evaporation leaving the crude product as a solid. Almost all the excess iodine could be removed from the mixture by sublimation under reduced pressure avoiding the need for quenching with sodium metabisulfite and allowing further reuse of reagents. This solvent-free approach to the iodination of ortho-Carboranes is feasible and appears to be fairly generic for the synthesis of tetraiodinated products.
Facile electrophilic iodination of icosahedral carboranes. Synthesis of carborane derivatives with boron - Carbon bonds via the palladium-catalyzed reaction of diiodocarboranes with grignard reagents
Zheng, Zhiping,Jiang, Wei,Zinn, Alfred A.,Knobler, Carolyn B.,Hawthorne, M. Frederick
, p. 2095 - 2100 (2008/10/08)
Electrophilic diiodination reactions of icosahedral closo-1,2-C2B10H12 and closo-1,7-C2B10H12 using 2 molar equiv of iodine monochloride in the presence of catalytic amounts of aluminum chloride yielded the corresponding closo-9,12-I2-1,2-C2B10H10 and closo-9,10-I2-1,7-C2B10H10 complexes in excellent yields. Palladium-mediated cross-coupling reactions of these diiodocarboranes with a variety of alkyl, aralkyl, and aryl Grignard reagents were reinvestigated, and it was demonstrated that the addition of copper(I) iodide as a cocatalyst is crucial to the success of this reaction. A reaction mechanism involving the initial formation of binary organocopper species (RCu; R = alkyl, aralkyl, aryl) followed by the reaction of (σ-carboranyl)palladium iodides (L2Pd(CbI)I and L2Pd(CbR)I; L = PPh3, Cb = closo-1,2-C2B10H10, closo-1,7-C2B10H10) via a four-centered transition state is proposed. The molecular structures of closo-9,10-I2-1,7-C2B10H10, 1, and closo-9,10-(C6H5)2-1,7-C2B 10H10, 10, have been determined. Crystallographic data are as follows: for 1, monoclinic, space group P21/c, a = 13.2719-(6) A?, b = 14.9718(6) A?, c = 13.4734(6) A?, β = 114.211(1)°, V = 2441.7(3) A?3, Z = 8, ρcalcd = 2.15 g cm-3, R = 0.043, Rw = 0.064; for 10, tetragonal, space group I41/a, a = 9.446(2) A?, c = 39.949(8) A?, V = 3564.1(1) A?3, Z = 8, ρcalcd = 1.10 g cm-3, R = 0.056, Rw = 0.063.
