Pentaborate Anions Research Articles

Novel approach to boron-10 enriched decaborane(14): an important advance in synthetic boron hydride chemistry

The oxidative polyhedral cage-fusion reaction of the sodium or lithium salt of the B-10 enriched pentaborate anion, [10B5H8]−, with anhydrous FeCl3, NiCl2, Br2, or C5H11Br, followed by room temperature sublimation of the product, produced 10B10H14 (3) in 52–65% yields.

Formation of the Decahydro(trimethylphosphine)pentaborate(1-) Anion and an Isomer of Trimethylphosphine-Pentaborane(11)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTFormation of the Decahydro(trimethylphosphine)pentaborate(1-) Anion and an Isomer of Trimethylphosphine-Pentaborane(11)Peter Grundt and Goji KodamaCite this: Inorg. Chem. 1994, 33, 9, 2056–2059Publication Date (Print):April 1, 1994Publication History Published online1 May 2002Published inissue 1 April 1994https://doi.org/10.1021/ic00087a051RIGHTS & PERMISSIONSArticle Views75Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (2 MB) Get e-Alerts Get e-Alerts

N(nPr)4[B5O6(OH)4][B(OH)3]2 and N(nBu)4[B5O6(OH)4][B(OH)3]2: Clathrates with a diamondoid arrangement of hydrogen-bonded pentaborate anions

Single-crystal X-ray structure analyses of N(nPr)4[B5O6(OH)4][B(OH)3]2,1, and N(nBu)4 [B5O6(OH)4][B(OH)3]2,2, reveal that these materials are novel clathrates, the isotypic host structures of which are three-dimensional assemblies of hydrogen-bonded [B5O6(OH)4]− ionsand B(OH)3 molecules. The assembly of only the pentaborate anions is a distorted (i.e., along [102] elongated) fourconnected diamond-related network. The N(nPr)4+ and N(nBu)4+ ions are trapped within the complex three-dimensional channel systems of the host frameworks. Both1 and2 crystallize monoclinically with space groupP21/c andZ=4. The cell constants are:1:a=13.592(5),b=12.082(2),c=17.355(6) A, β=106.60(2)° (298K);2:a=13.874(3),b=12.585(1),c=17.588(4) A, β=107.04(1)° (238 K). The results obtained by both11B and13C MAS NMR spectroscopy are discussed. Thermogravimetric studies under a flowing inert-gas atmosphere suggest that water, stemming from polycondensation of the hydrous borate species, is released from the clathrates at ca. 443 K (1) and 398 K (2) before the decomposition of the organic cations starts at ca. 603 K (1) and 603 K (2).

Clathrates with Three-Dimensional Host Structures of Hydrogen-Bonded Pentaborate [B5O6(OH)4]- Ions: Pentaborates with the Cations NMe4 +, NEt4 +, NPhMe3 + and pipH+ (pipH+ = Piperidinium)

X-ray structure analyses of crystalline [NMe4][B5O6(OH)4] · nH2O with n ≈ 0.25-0.50 (1), [NEt4][B5O6(OH)4] (2), [NPhMe3][B5O6(OH)4] (3), and [pipH][B5O6(OH)4] (4) reveal that these materials are novel clathrates with closely related three-dimensional host structures built up of hydrogen-bonded oligomeric pentaborate [B5O6(OH)4]- ions. The organic cations and water molecules (in 1) occupy as guest species large straight channel-like voids of nearly rectangular cross-section. Compound 1 crystallizes monoclinically with space group P2,/c (Z = 4); the compounds 2,3 and 4, which possess the same host-structure topology, crystallize triclinically with space group P1̄ (Z = 2). 11B-MAS NMR spectra allow the detection of small angular distortions in the pentaborate anions caused by the specific hydrogen bonding in the host frameworks. Upon heating the compounds on a thermobalance in a dynamic inert gas atmosphere dehydration occurs at temperatures of 563 K (1), 543 K (2), 558 K (3) and 523 K (4) before degradation of the organic cations starts at temperatures of 633 K (1), 623 K (2), 623 K (3) and 613 K (4).

Sborgit und β-Sborgit — eine zweite synthetische Modifikation von Na[B5O6(OH)4] · 3 H2O / Sborgit and β-Sborgit – a Second Synthetic Modification of Na[B5O6(OH)4] · 3 H2O

In crystallization experiments for silver borate hydrates from solutions of borax, boric acid, and silver nitrate, a mixture of sborgite and a second modification — named by us “β-sborgite” — have been found besides excess H3BO3 and a microcrystalline silver borate. Both modifications contain the same distorted pentaborate ion [B5O6(OH)4]-. Both Na+ ions in the asymmetric unit are in special positions along the binary axis; one, Na(1), is octahedrally coordinated by four H2O molecules and two OH groups, the other one, Na(2), is tetrahedrally coordinated by two H2O molecules, two OH groups and — at longer distances — with two bridging oxygen atoms of the pentaborate unit. The different angles — only a small rotation on the b-axis — of the pentaborate anions between an identical matrix of Na-cations give rise to the two different modifications.

Röntgenographische Strukturuntersuchung von Cäsiumhexaoxo-tetrahydroxo-pentaborat-2-dimethylsulfoxid / X-ray Study of the Structure of Cesiumhexaoxo-tetrahydroxo-pentaborate-2-dimethyl Sulfoxide

The compound Cs[B5O6(OH)4] · 2 DMSO was prepared by hydrolysis of tris(methoxy)-borane in organic solvents with small amounts of water in presence of cesium tert-butylate and recrystallized in DMSO (dimethyl sulfoxide). Cs[B5O6(OH)4] · 2 DMSO crystallizes in the monoclinic space group Ρ21/a with a= 9.593(2), b=19.179(4), c= 11.585(2) A, β= 119.99(2)° and Ζ = 4. The crystal structure was determined by single-crystal diffractometer data and refined to a conventional R value of 9.9%. The crystal structure consists of chains of pentaborate anions [B5O6(OH)4]- linked by hydrogen bonds. The cesium cation and the DMSO molecules join the chains to sheets by coordination and hydrogen bonds respectively.

Crystal structure of 3Bi 2O 3:5B 2O 3. A new type of polyborate anion (B 5O 11) 7−

Single crystals of 3Bi 2O 3:5B 2O 3 have been obtained from the melt and subsequent devitrification of the glassy compound, at 450°C during 90 hr. The compound is orthorhombic, space group Pnma with two formula units in the cell. The lattice parameters are a = 6.532 Å, b = 7.733 Å, c = 18.566 Å. The structure was solved from a complete set of three-dimensional Mo K α diffractometer data, the final R being 0.097. The structure is made up of Bi 3+ cations and O 2− and (B 5O 11) 7− anions. The pentaborate anion is formed by two BO 4 tetrahedra and three BO 3 triangles, sharing edges and corners. An oxygen that is not bonded to any boron is in the center of a three-bismuth triangle. Two independent bismuth atoms are present in the structure. Bi(1) has six first-neighbor oxygens with an average BiO distance of 2.44 Å and Bi(2) has either six or seven oxygens in the first coordination sphere with an average BiO distance of 2.43 or 2.80 Å, respectively.