Diborane(2)

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Diborane(2)
Diborene.svg
Names
Other names
Diborene
Identifiers
3D model (JSmol)
ChemSpider
PubChem CID
  • InChI=1S/B2H2/c1-2/h1-2H
    Key: HWGHUECIBSMKRW-UHFFFAOYSA-N
  • B=B
Properties
B2H2
Molar mass 23.64 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Diborane(2) or diborene is a theoretical/hypothetical inorganic compound with the formula B2H2. Diborenes also refers to a series of molecules with a formula R:(BH)=(BH):R, where R is an organic group. [1] B2H2 are unstable under ambient conditions. They are synthesized by pulsed laser ablation of boron in a mixed hydrogen-argon gas atmosphere. Upon cooling the mixture, the argon gas changes into a solid, thereby stabilizing the trapped diboranes. [2] [3]

B2H2 is a linear molecule with a triplet ground state, as revealed by electron paramagnetic resonance, [2] and shows an antisymmetric stretching mode at 2679.9 cm–1. [3]

Related Research Articles

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<span class="mw-page-title-main">Diborane</span> Chemical compound

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<span class="mw-page-title-main">Borazine</span> Boron compound

Borazine, also known as borazole, is a non-polar inorganic compound with the chemical formula B3H6N3. In this cyclic compound, the three BH units and three NH units alternate. The compound is isoelectronic and isostructural with benzene. For this reason borazine is sometimes referred to as “inorganic benzene”. Like benzene, borazine is a colourless liquid with an aromatic smell.

<span class="mw-page-title-main">Ammonia borane</span> Chemical compound

Ammonia borane (also systematically named amminetrihydridoboron), also called borazane, is the chemical compound with the formula H3NBH3. The colourless or white solid is the simplest molecular boron-nitrogen-hydride compound. It has attracted attention as a source of hydrogen fuel, but is otherwise primarily of academic interest.

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Titanium(IV) hydride is an inorganic compound with the empirical chemical formula TiH
4
. It has not yet been obtained in bulk, hence its bulk properties remain unknown. However, molecular titanium(IV) hydride has been isolated in solid gas matrices. The molecular form is a colourless gas, and very unstable toward thermal decomposition. As such the compound is not well characterised, although many of its properties have been calculated via computational chemistry.

Chromium(II) hydride, systematically named chromium dihydride and poly­(dihydridochromium) is pale brown solid inorganic compound with the chemical formula (CrH
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n
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Uranium(IV) hydride is a chemical compound with the chemical formula UH4, a metal hydride composed of uranium and hydrogen.

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3
. The preparation of borane carbonyl, BH3(CO), played an important role in exploring the chemistry of boranes, as it indicated the likely existence of the borane molecule. However, the molecular species BH3 is a very strong Lewis acid. Consequently, it is highly reactive and can only be observed directly as a continuously produced, transitory, product in a flow system or from the reaction of laser ablated atomic boron with hydrogen.

<span class="mw-page-title-main">1,2-Dimethyldiborane</span> Chemical compound

1,2-Dimethyldiborane is an organoboron compound with the formula [(CH3)BH2]2. Structurally, it is related to diborane, but with methyl groups replacing terminal hydrides on each boron. It is the dimer of methylborane, CH3BH2, the simplest alkylborane. 1,2-Dimethyldiborane can exist in a cis- and a trans arrangement. 1,2-Dimethyldiborane is an easily condensed, colorless gas that ignites spontaneously in air.

<span class="mw-page-title-main">Tetramethyldiborane</span> Chemical compound

Dimethylborane, (CH3)2BH is the simplest dialkylborane, consisting of a methyl group substituted for a hydrogen in borane. As for other boranes it normally exists in the form of a dimer called tetramethyldiborane or tetramethylbisborane or TMDB ((CH3)2BH)2. Other combinations of methylation occur on diborane, including monomethyldiborane, trimethyldiborane, 1,2-dimethylborane, 1,1-dimethylborane and trimethylborane. At room temperature the substance is at equilibrium between these forms. The methylboranes were first prepared by H. I. Schlesinger and A. O. Walker in the 1930s.

<span class="mw-page-title-main">Trimethyldiborane</span> Chemical compound

Trimethyldiborane, (CH3)3B2H3 is a molecule containing boron carbon and hydrogen. It is an alkylborane, consisting of three methyl group substituted for a hydrogen in diborane. It can be considered a mixed dimer: (CH3)2BH2BH(CH3) or dimethylborane and methylborane. called 1,2-dimethyldiborane. Other combinations of methylation occur on diborane, including monomethyldiborane, 1,2-dimethyldiborane, tetramethyldiborane, 1,1-dimethylborane and trimethylborane. At room temperature the substance is at equilibrium between these forms, so it is difficult to keep it pure. The methylboranes were first prepared by H. I. Schlesinger and A. O. Walker in the 1930s.

<span class="mw-page-title-main">Methyldiborane</span> Chemical compound

Methyldiborane, CH3B2H5, or monomethyldiborane is the simplest of alkyldiboranes, consisting of a methyl group substituted for a hydrogen in diborane. As with other boranes it exists in the form of a dimer with a twin hydrogen bridge that uses three-center two-electron bonding between the two boron atoms, and can be imagined as methyl borane (CH3BH2) bound to borane (BH3). Other combinations of methylation occur on diborane, including 1,1-dimethylborane, 1,2-dimethyldiborane, trimethyldiborane, tetramethyldiborane, and trimethylborane (which is not a dimer). At room temperature the substance is at equilibrium between these molecules.

Neon compounds are chemical compounds containing the element neon (Ne) with other molecules or elements from the periodic table. Compounds of the noble gas neon were believed not to exist, but there are now known to be molecular ions containing neon, as well as temporary excited neon-containing molecules called excimers. Several neutral neon molecules have also been predicted to be stable, but are yet to be discovered in nature. Neon has been shown to crystallize with other substances and form clathrates or Van der Waals solids.

Argon compounds, the chemical compounds that contain the element argon, are rarely encountered due to the inertness of the argon atom. However, compounds of argon have been detected in inert gas matrix isolation, cold gases, and plasmas, and molecular ions containing argon have been made and also detected in space. One solid interstitial compound of argon, Ar1C60 is stable at room temperature. Ar1C60 was discovered by the CSIRO.

<span class="mw-page-title-main">1,1-Dimethyldiborane</span> Chemical compound

1,1-Dimethyldiborane is the organoboron compound with the formula (CH3)2B(μ-H)2BH2. A pair of related 1,2-dimethyldiboranes are also known. It is a colorless gas that ignites in air.

Borane(1), boron monohydride, hydridoboron or borylene is the molecule with the formula BH. It exists as a gas but rapidly degrades when condensed. By contrast, the cluster [[B12H12]]2- (dodecaborate), which has very similar empirical formula, forms robust salts.

<span class="mw-page-title-main">Boron triazide</span> Chemical compound

Boron triazide, also known as triazidoborane, is a thermally unstable compound of boron and nitrogen with a nitrogen content of 92.1 %. Formally, it is the triazido derivative of borane and is a covalent inorganic azide. The high-energy compound, which has the propensity to undergo spontaneous explosive decomposition, was first described in 1954 by Egon Wiberg and Horst Michaud of the University of Munich.

References

  1. Yuzhong Wang, Brandon Quillian, Pingrong Wei, Chaitanya S. Wannere, Yaoming Xie, R. Bruce King, Henry F. Schaefer, III, Paul v. R. Schleyer, and Gregory H. Robinson (2007). "A Stable Neutral Diborene Containing a B=B Double Bond". J. Am. Chem. Soc. 129 (41): 12412–12413. doi:10.1021/ja075932i. PMID   17887683.{{cite journal}}: CS1 maint: uses authors parameter (link)
  2. 1 2 Knight, Lon B.; Kerr, Kelly; Miller, P. K.; Arrington, C. A. (1995). "ESR Investigation of the HBBH(X3Σ) Radical in Neon and Argon Matrices at 4 K. Comparison with ab Initio SCF and Cl Calculations". The Journal of Physical Chemistry. 99 (46): 16842–16848. doi:10.1021/j100046a009.
  3. 1 2 Tague, Thomas J.; Andrews, Lester (1994). "Reactions of Pulsed-Laser Evaporated Boron Atoms with Hydrogen. Infrared Spectra of Boron Hydride Intermediate Species in Solid Argon". Journal of the American Chemical Society. 116 (11): 4970–4976. doi:10.1021/ja00090a048.