Tetraborane

Tetraborane
IUPAC name

tetraborane(10)
arachno-B4H10
Identifiers
CAS number 18283-93-7
ChemSpider 21865171 Y
ChEBI CHEBI:33592
Properties[1]
Molecular formula B4H10
Molar mass 53.32 g/mol
Appearance colourless gas
Density 2.3 kg m-3 (gas)
Melting point

−120.8 °C
Boiling point

18 °C
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Tetraborane, or to be more precise tetraborane(10) or arachno-B4H10 was the first boron hydride compound to be classified by Stock and Messenez in 1912 and was first isolated by Alfred Hock. It has a relatively low boiling point at 18°C and is liquid at room temperature. Tetraborane gas is foul smelling and toxic.

Contents

Safety

Because it is easily oxidized it must be kept under vacuum. Tetraborane ignites when it comes in contact with air, oxygen, and nitric acid. Boranes in general including tetraborane have been deemed very toxic and are biologically destructive. A study consisting of small daily exposure of the chemical to rabbits and rats resulted in fatality[2]

Preparation

Tetraborane can be produced via a reaction between acid and magnesium, aluminum, or beryillium borides. Hydrolysis of magnesium boride, hydrogenation of of boron halide (at high temperatures) and the pyrolysis of diborane also produce tetraborane. The hydrolysis of magnesium boride was one of the first reactions to give a high yield(14%) of tetraborane. Phosphoric acid proved to be the most efficient acid (other than hydrochloric and sulfuric acid)in the reaction with magnesium boride. Reduction of boron halides with hydrogen in the presence of metal hydride at high temperatures also produces tetraborane[3]

References

  1. ^ Weast, Robert C., ed (1981). CRC Handbook of Chemistry and Physics (62nd ed.). Boca Raton, FL: CRC Press. p. B-84. ISBN 0-8493-0462-8. .
  2. ^ http://voh.chem.ucla.edu/vohtar/spring05/classes/172/pdf/p21-30Borane.pdf
  3. ^ Dain, C. J., Downs, A. J., Laurenson, G. S., & Rankin, D. W. (1981). The Molecular Structure of Tetraborane(10) in the Gas Phase as determined by a Joint Analysis of Electron-diffraction and Microwave Data. Journal of the Chemical Society, 472-477.

http://pubs.acs.org/doi/pdf/10.1021/ic049558o3 http://voh.chem.ucla.edu/vohtar/spring05/classes/172/pdf/p21-30Borane.pdf

External links