Diborane Final AEGL Document
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Thermodynamic Hydricity of Small Borane Clusters and Polyhedral Closo-Boranes
molecules Article Thermodynamic Hydricity of Small Borane Clusters y and Polyhedral closo-Boranes Igor E. Golub 1,* , Oleg A. Filippov 1 , Vasilisa A. Kulikova 1,2, Natalia V. Belkova 1 , Lina M. Epstein 1 and Elena S. Shubina 1,* 1 A. N. Nesmeyanov Institute of Organoelement Compounds and Russian Academy of Sciences (INEOS RAS), 28 Vavilova St, 119991 Moscow, Russia; [email protected] (O.A.F.); [email protected] (V.A.K.); [email protected] (N.V.B.); [email protected] (L.M.E.) 2 Faculty of Chemistry, M.V. Lomonosov Moscow State University, 1/3 Leninskiye Gory, 119991 Moscow, Russia * Correspondence: [email protected] (I.E.G.); [email protected] (E.S.S.) Dedicated to Professor Bohumil Štibr (1940-2020), who unfortunately passed away before he could reach the y age of 80, in the recognition of his outstanding contributions to boron chemistry. Academic Editors: Igor B. Sivaev, Narayan S. Hosmane and Bohumír Gr˝uner Received: 6 June 2020; Accepted: 23 June 2020; Published: 25 June 2020 MeCN Abstract: Thermodynamic hydricity (HDA ) determined as Gibbs free energy (DG◦[H]−) of the H− detachment reaction in acetonitrile (MeCN) was assessed for 144 small borane clusters (up 2 to 5 boron atoms), polyhedral closo-boranes dianions [BnHn] −, and their lithium salts Li2[BnHn] (n = 5–17) by DFT method [M06/6-311++G(d,p)] taking into account non-specific solvent effect (SMD MeCN model). Thermodynamic hydricity values of diborane B2H6 (HDA = 82.1 kcal/mol) and its 2 MeCN dianion [B2H6] − (HDA = 40.9 kcal/mol for Li2[B2H6]) can be selected as border points for the range of borane clusters’ reactivity. -
Diborane (B2H6) 2 Heavier Boron Hydrides in the Form of Volatile Liquids Such As
Even in the absence of contamination, diborane is so reactive that it will slowly decompose by itself, forming H gas and Diborane (B2H6) 2 heavier boron hydrides in the form of volatile liquids such as Storage and Delivery B5H9 and sublimable solids such as B10H14. These heavier hydrides are delivered with the gas and can cause Air Products supplies a wide range of gases and chemicals contamination of the process and fouling of the delivery system that are used for integrated circuit, flat panel display and components. Figure 1 shows the internals of the first stage of photovoltaic device manufacturing. Understanding the proper a two-stage gas regulator that was fouled by B10H14 deposits. storage and handling requirements of these specialty materials is essential to obtain consistent results and to ensure the highest level of process safety. In this technical bulletin, we will provide the user with some of the knowledge required for its effective storage and use. Figure 1: Picture of the first stage of diborane mixture regulator Diborane (formula B2H6) is a colorless, spontaneously fouled with solid decomposition products. flammable (pyrophoric) gas. It burns rapidly in air and reacts vigorously with water with the evolution of heat. The gas has The gas-phase decomposition rate of diborane was shown to a distinct, noxious odor and is extremely toxic by inhalation or increase with concentration and with temperature. Pure by skin exposure. Because of these hazards, it is essential diborane is so reactive in its pure state that it may only be that all gas handling systems used for diborane be tightly stored or transported if surrounded with dry ice to prevent rapid sealed and carefully leak checked. -
276262828.Pdf
FUNDAMENTAL STUDIES OF CATALYTIC DEHYDROGENATION ON ALUMINA-SUPPORTED SIZE-SELECTED PLATINUM CLUSTER MODEL CATALYSTS by Eric Thomas Baxter A dissertation submitted to the faculty of The University of Utah in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Chemistry The University of Utah May 2018 Copyright © Eric Thomas Baxter 2018 All Rights Reserved T h e U n iversity of Utah Graduate School STATEMENT OF DISSERTATION APPROVAL The dissertation of Eric Thomas Baxter has been approved by the following supervisory committee members: Scott L. Anderson , Chair 11/13/2017 Date Approved Peter B. Armentrout , Member 11/13/2017 Date Approved Marc D. Porter , Member 11/13/2017 Date Approved Ilya Zharov , Member 11/13/2017 Date Approved Sivaraman Guruswamy , Member 11/13/2017 Date Approved and by Cynthia J. Burrows , Chair/Dean of the Department/College/School of Chemistry and by David B. Kieda, Dean of The Graduate School. ABSTRACT The research presented in this dissertation focuses on the use of platinum-based catalysts to enhance endothermic fuel cooling. Chapter 1 gives a brief introduction to the motivation for this work. Chapter 2 presents fundamental studies on the catalytic dehydrogenation of ethylene by size-selected Ptn (n = 4, 7, 8) clusters deposited onto thin film alumina supports. The model catalysts were probed by a combination of experimental and theoretical techniques including; temperature-programmed desorption and reaction (TPD/R), low energy ion scattering spectroscopy (ISS), X-ray photoelectron spectroscopy (XPS), plane wave density-functional theory (PW-DFT), and statistical mechanical theory. It is shown that the Pt clusters dehydrogenated approximately half of the initially adsorbed ethylene, leading to deactivation of the catalyst via (coking) carbon deposition. -
Boranes: Physical & Chemical Properties, Encyclopaedia of Occupational Health and Safety, Jeanne Mager Stellman, Editor-In
Boranes: Physical & chemical properties, Encyclopaedia of Occupational Health and Safety, Jeanne Mager Stellman, Editor-in-Chief. International Labor Organization, Geneva. 2011. Chemical Name Colour/Form Boiling Point Melting Molecular Solubility in Relative Density Relative Vapour Inflam. Flash Auto CAS-Number (°C) Point (°C) Weight Water (water=1) Vapour Pressure/ Limits Point (°C) Ignition Density (Kpa) Point (°C) (air=1) BORON polymorphic: alpha- 2550 2300 10.81 insol Amorphous, 1.56x 580 3 -5 7440-42-8 rhombohedral form, clear 2.3 g/cm ; 10 red crystals; beta- alpha-- @ 2140 °C rhombohedral form, black; rhombohedral, - alpha-tetragonal form, 2.46 g/cm3; - black, opaque crystals with alpha-- metallic luster; amorphous tetragonal, - form, black or dark brown 2.31 g/cm3; - powder; other crystal beta-rhom- forms known bohedral, - 2.35 g/cm3 BORIC ACID, DISODIUM powder or glass-like 1575 741 201.3 2.56 g/100 g 2.367 SALT plates; white, free-flowing 1330-43-4 crystals; light grey solid BORON OXIDE rhombic crystals; 1860 450 69.6 2.77 g/100 g 1.8 1303-86-2 colourless, (amorphous); semitransparent lumps or 2.46 hard, white crystals (crystalline) BORON TRIBROMIDE colourless liquid 90 -46.0 250.57 reacts 2.6431 8.6 5.3 10294-33-4 @ 18.4 °C/4 °C @ 14 °C BORON TRICHLORIDE 12.5 -107 117.16 1.35 4.03 2.99 Pa 10294-34-5 @ 12 °C/4 @ 12.4 °C BORON TRIFLUORIDE colourless gas -99.9 -126.8 67.82 reacts 3.08g/1.57 l 2.4 10 mm Hg 7637-07-2 @ 4 °C @ -141 °C. -
Identification of Diborane(4) with Bridging B–H–B Bonds
Chemical Science View Article Online EDGE ARTICLE View Journal | View Issue Identification of diborane(4) with bridging B–H–B bonds† Cite this: Chem. Sci.,2015,6, 6872 Sheng-Lung Chou,a Jen-Iu Lo,a Yu-Chain Peng,a Meng-Yeh Lin,a Hsiao-Chi Lu,a Bing-Ming Cheng*a and J. F. Ogilvieb The irradiation of diborane(6) dispersed in solid neon at 3 K with tunable far-ultraviolet light from a Received 17th July 2015 synchrotron yielded a set of IR absorption lines, the pattern of which implies a carrier containing two Accepted 14th August 2015 boron atoms. According to isotope effects and quantum-chemical calculations, we identified this new DOI: 10.1039/c5sc02586a species as diborane(4), B2H4, possessing two bridging B–H–B bonds. Our work thus establishes a new www.rsc.org/chemicalscience prototype, diborane(4), for bridging B–H–B bonds in molecular structures. Introduction The B–H–B linkage in these compounds is considered to be an atypical electron-decient covalent chemical bond.7 Creative Commons Attribution 3.0 Unported Licence. The structure that B2H6 adopts in its electronic ground state According to calculations, diborane species possessing less and most stable conformation contains two bridging B–H–B than 6 hydrogen atoms and bridging B–H–Bbondscan 8–13 bonds, and four terminal B–H bonds. Although Bauer, from exist, but all possible candidates are transient species, experiments with the electron diffraction of gaseous samples in difficult to prepare and to identify. Since the pioneering work the laboratory of Pauling and Brockway, favoured a structure of involving absorption spectra of samples at temperatures less 14,15 diborane(6) with a central B–B bond analogous to that of than 100 K, many free radicals and other unstable 16–20 ethane,1 Longuet-Higgins deduced the bridged structure for compounds dispersed in inert hosts have been detected. -
Boranes: Structure & Bonding
18-Aug-20 Boranes: Structure & Bonding PROF. K.K. UPADHYAY DEPARTMENT OF CHEMISTRY INSTITUTE OF SCIENCE, BHU VARANASI - 221005 An Introduction to Boranes . For undergraduate students, boranes means only diborane which is not true. Boranes means electron deficient molecules but probably that is not true. Boranes are a class of compounds comprising of several hundreds of compounds ranging from simple to polyhedral to macro polyhedral types having intriguing structures. 1 18-Aug-20 10 11 . Boron is an element with atomic no. 5 having two isotopes 5B (20%) and 5B (80%). It occupies group XIII and is a p-block element. .Boranes are binary compounds of boron and hydrogen and are the fourth most extensive group of hydrides after the Carbon, Phosphorous and Silicon hydrides. BH 3 is the simplest of all the boranes but non-existent. B2H6 is the dimer of BH 3 and is the most primitive among the existing boranes. Boranes are not found in the nature. These are always synthesised in the laboratory. Very first synthesis was carried out in 19 th century by protolysis of metal borides. 2Mg 3B2 + 12HCl 6MgCl 2 + mixture of boranes . But neither correctly analysed nor identified. 2 18-Aug-20 . The first systematic study of boranes was performed by Alfred stock during the year 1912-1936. He used Schlenk line technique for the synthesis of boranes in a systematic way. Alfred Stock . He studied nature, stoichiometry and reactivity of boranes in a systematic way. 3 NaBH 4 + 4 BF 3→ 3 NaBF 4 + mixture of boranes BCl 3 + 3 H 2 → mixture of boranes + 3 HCl - 3- BH 4 + BX 3 → mixture of boranes + HBX (X = Cl, Br) Schlenk line 2x4 + 1x6 = 14 electrons 2x3 + 1x6 = 12 electrons . -
Reactions of Titanium Imides and Hydrazides with Boranes Simona Mellino,† Laura C
This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited. Article pubs.acs.org/Organometallics Reactions of Titanium Imides and Hydrazides with Boranes Simona Mellino,† Laura C. Stevenson,† Eric Clot,*,‡ and Philip Mountford*,† † Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford OX1 3TA, U.K. ‡ Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM-ENSCM, Universitéde Montpellier, cc 1501, Place Eugené Bataillon, F-34095 Montpellier Cedex 5, France *S Supporting Information ABSTRACT: We report the first reactions of titanium imido, alkylidene hydrazido, and dimethylhydrazido compounds with the F F * i boranes H2BTex, 9-BBN, HBAr 2, and HBPin (Tex = tert-hexyl; Ar =C6F5). Reactions of Cp Ti{MeC(N Pr)2}(NTol) with F * i ′ − H2BTex, 9-BBN, or HBAr 2 resulted in the hydride-bridged adducts Cp Ti{MeC(N Pr2)2}{N(Tol)HBRR } without B H bond * i F β cleavage. Cp Ti{MeC(N Pr)2}(NNCPh2)(4) reacted with HBAr 2 via a sequence of steps involving adducts at the - and then α − -nitrogen of the NNCPh2 ligand, before slow 1,2-addition of B H across the N CPh2 double bond of 4, forming * i F Cp Ti{MeC(N Pr)2}{NN(BAr 2)CHPh2}(17). The other boranes reacted immediately with 4 to form homologues of 17. fi * i These products are the rst examples of borylhydrazido(2-) complexes. Reaction of Cp Ti{MeC(N Pr2)2}(NNMe2)(2) with F * i F − HBAr 2 gave the hydride-bridged adduct Cp Ti{MeC(N Pr2)2}{N(NMe2)HBAr 2}, whereas with HBPin B H bond cleavage * i occurred to form the borylhydrazide(1-)-hydride Cp Ti{MeC(N Pr)2}(H){N(BPin)NMe2}. -
Innovation Infosheet Preparation of Amine Boranes, Ammonia Borane, and Phosphine Boranes
Innovation Infosheet Downloaded September 29, 2021 Preparation of Amine Boranes, Ammonia Borane, and Phosphine Boranes Track Code: 2014-RAMA-66892 Categories: - Chemistry and Chemical Analysis Keywords: - Amine-Boranes - Chemistry and Chemical Analysis - Hydrogen Storage Amine and phosphine-boranes, the classic Lewis base-Lewis acid (LB-LA) pairs have been known and valued for over a century, with uses that include hydrogen storage applications. There are major drawbacks associated with current procedures for making amine-boranes, including low efficiency and other issues such as formation of highly unpleasant odors from the necessary reactions. In addition, removal of dimethyl sulfide for reuse of the solvent THF adds additional steps in the synthetic process. Therefore, as the demand for large quantities of amine- boranes increases, there is a need for more effective methods for making ammonia borane and amine-boranes. Researchers at Purdue University have developed several new procedures to efficiently make ammonia borane and amine boranes in large quantities. In addition, due to the stability of sodium borohydride (SBH) and ammonia borane in water, water can be used in the production process, allowing for an efficient, cost-effective synthesis of ammonia borane from SBH. Advantages: -Simplest possible synthesis of ammonia borane from sodium borohydride -Prepare ammonia-borane in large quantities Potential Applications: -Method for making a more pure ammonia borane and amine borane People: - Ramachandran, Padinjaremadhom V (Project -
Chapter 9 Hydrogen
Chapter 9 Hydrogen Diborane, B2 H6• is the simplest member of a large class of compounds, the electron-deficient boron hydrid Like all boron hydrides, it has a positive standard free energy of formation, and so cannot be prepared direct from boron and hydrogen. The bridge B-H bonds are longer and weaker than the tenninal B-H bonds (13: vs. 1.19 A). 89.1 Reactions of hydrogen compounds? (a) Ca(s) + H2Cg) ~ CaH2Cs). This is the reaction of an active s-me: with hydrogen, which is the way that saline metal hydrides are prepared. (b) NH3(g) + BF)(g) ~ H)N-BF)(g). This is the reaction of a Lewis base and a Lewis acid. The product I Lewis acid-base complex. (c) LiOH(s) + H2(g) ~ NR. Although dihydrogen can behave as an oxidant (e.g., with Li to form LiH) or reductant (e.g., with O2 to form H20), it does not behave as a Br0nsted or Lewis acid or base. It does not r with strong bases, like LiOH, or with strong acids. 89.2 A procedure for making Et3MeSn? A possible procedure is as follows: ~ 2Et)SnH + 2Na 2Na+Et3Sn- + H2 Ja'Et3Sn- + CH3Br ~ Et3MeSn + NaBr 9.1 Where does Hydrogen fit in the periodic chart? (a) Hydrogen in group 1? Hydrogen has one vale electron like the group 1 metals and is stable as W, especially in aqueous media. The other group 1 m have one valence electron and are quite stable as ~ cations in solution and in the solid state as simple 1 salts. -
Prep Aration and Pro Perties of Trifluoromethyl• Boranes Everett Duane Baker a Thesis Oregon State College Master of Science
PREP ARATION AND PRO PERTIES OF TRIFLUOROMETHYL• BORANES by EVERETT DUANE BAKER A THESIS submitted to OREGON STATE COLLEGE in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE June 1961 APTBOVEDT Redacted for Privacy Arroolat. Profilts sf Chrrl. tlt In 0hrr.gr of, l{rt or Redacted for Privacy Ghrlrarn of Drpuhcat of Chralttry Redacted for Privacy Chr lrun Sobool Orrdurtr Comtttrr Redacted for Privacy Dorn of &rrductr Scbool Drtr thrrlr 1r prrcntod )g Au2a2t l%O Iypod by LrAnna Ermlr ACKNOWLEDGMENT Tbe author wishes to express his sincere appre ciation to Dr- Theran D. Parsons tor h1s guidance and encouragement throughout tha course of this inves tigation. The material aid ot the Office ot Naval Research fellowship is acknowledged w1th appreciation. TABLE OF CONTENTS Page I. INTRODUCTION ' • 1 • • ... • • • • • • • • • • • • II. EXPERIMENTAL • •• ,, ... • ••• • • • .... • • • 1) A~ Appara tue and Eqatpme.nt. .. • • • • • • • • • • 1) B. Reagen t8 • • • • • • • • • • • • • • • • • • .1) c. P~epal!lt1ona and ·lteactiona • • • • • , , • • .15 Figure I , • • • • ·• ... ·• • • • • • • • • • .16 Table I • •· • • • • • • , • • • • • • • • ~ Figure 2 • • • • • • • • • • • • • • • • • •. :~~ lli. DISCUSSION AND CONCLUSIONS ·• .. • • . ·• . .29 IV, BIB.LIOGRAl?iY • • • • .• • • • • • • • • • • • • • •34 PREPARATION AND PROPERTIES OF TRIFLUROMETHYL-BOR ANES I. INTRODUCTION The elucidatio.n or the struct\ll'es of the boron hydrides and their ~erivatives, and of certain compounds of aluminum, has caused great interest in electron deficient bonding. Lipscomb (14) reviewed the s t ructures ot the boron hydrides. Evidence was cited which s how s that diborane has a structure in which. two of the hydrogen atoms form a bridge between the two boron atoms: H H H \. 1\ I B B / \. / \ H H H The grouping of the atoms bonde d to a boron a tom is ap prox imately tetrahedral in configuration. -
Green Hypergolic Fuels with Consistently Low Ignition Delays P
DOI: 10.1002/chem.201405224 Communication & Propellants Amine–Boranes: Green Hypergolic Fuels with Consistently Low Ignition Delays P. Veeraraghavan Ramachandran,*[a] Ameya S. Kulkarni,[a] Mark A. Pfeil,[b] Jacob D. Dennis,[b] Jared D. Willits,[b] Stephen D. Heister,[b] Steven F. Son,[c] and Timothe L. Pourpoint[b] ergetic influence of several reactions.[5] Interestingly, recent re- Abstract: Complexation of amines with borane converts ports have identified 38 amines such as N,N,N’,N’-tetramethyl- them to hypergols or decreases their ignition delays (IDs) ethylenediamine or 1,4-dimethylpiperazine (DMPZ, 1o), alone multifold (with white fuming nitric acid as the oxidant). or mixed with azido compounds, as potential hypergolic With consistently low IDs, amine–boranes represent fuels.[6] A modern trend in propellant research considers ionic a class of compounds that can be promising alternatives liquids (ILs) as future fuels for space applications.[7] The incor- to toxic hydrazine and its derivatives as propellants. A poration of boron in the IL structure[8] or as nanoparticle addi- structure–hypergolicity relationship study reveals the nec- tives[9] has provided new openings. IL solubilized boranes as essary features for the low ID. hypergolic fluids have been recently reported by Shreeve and Gao.[10] Their study identified triethylamine–borane as the most efficient “additive” for decreasing IDs of ILs.[10b] Chemical rockets used in space and missile applications For nearly a decade, we have been investigating amine–bor- depend on propellants -
Diborane (B2H6)
Safety Data Sheet Material Name: DIBORANE SDS ID: MAT06650 * * * Section 1 - PRODUCT AND COMPANY IDENTIFICATION * * * Material Name: DIBORANE Manufacturer Information MATHESON TRI-GAS, INC. General Information: 1-800-416-2505 150 Allen Road, Suite 302 Emergency #: 1-800-424-9300 (CHEMTREC) Basking Ridge, NJ 07920 Outside the US: 703-527-3887 (Call collect) Chemical Family metal, hydrides Synonyms MTG MSDS 111; BOROETHANE; BOROHYDRIDE; BIBORON HEXAHYDRIDE; DIBORANE(6); UN 1911; B2H6; RTECS: HQ9275000 Product Use industrial Usage Restrictions none known * * * Section 2 - HAZARDS IDENTIFICATION * * * EMERGENCY OVERVIEW Color: colorless Physical Form: gas Odor: irritating odor Health Hazards: potentially fatal if inhaled, respiratory tract burns, skin irritation, eye irritation Physical Hazards: May explode when heated. Flammable gas. May cause flash fire. ____________________________________________________________ Page 1 of 11 Issue Date: 12/15/2009 Revision: 1.0200 Print Date: 2/8/2010 Safety Data Sheet Material Name: DIBORANE SDS ID: MAT06650 POTENTIAL HEALTH EFFECTS Inhalation Short Term: burns, difficulty breathing, headache, dizziness, blurred vision, lung congestion, kidney damage, liver damage, death Long Term: same as effects reported in short term exposure Skin Short Term: irritation (possibly severe) Long Term: no information is available Eye Short Term: irritation (possibly severe) Long Term: no information is available Ingestion Short Term: no information on significant adverse effects Long Term: no information is available * * * Section 3 - COMPOSITION / INFORMATION ON INGREDIENTS * * * CAS Component Percent 19287-45-7 DIBORANE 100.0 * * * Section 4 - FIRST AID MEASURES * * * Inhalation If adverse effects occur, remove to uncontaminated area. Give artificial respiration if not breathing. If breathing is difficult, oxygen should be administered by qualified personnel.