Diborane(4)

Diborane(4)
Identifiers
18099-45-1 YesY
3D model (Jmol) Interactive image
ChEBI CHEBI:38288 YesY
24760
PubChem 29529
Properties
B
2H
4
Molar mass 25.65 g·mol–1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YesYN ?)
Infobox references

Diborane(4) (systematically named di-μH-catena-diborane(4) and di-μ-hydrido-bis(hydridoboron)(B—B)) is a inorganic compound with the chemical formula B
2H
4.[1][2]

Structure and bonding

Computational studies predict two structures, both of which contain a boron–boron bond. In the ground state, there are two hydrogens bridging the two boron atoms via three-centre two-electron bonds in addition to one additional hydrogen on each boron. The electrons of boron–boron bond are unusually localized to a region between these two atoms, creating a notable negative charge on the side of the B–B axis away from the hydrogen bridges. This non-nuclear attractor may be involved in interactions with other molecules as an electron-donor.[2]

Bonding and geometry of the excited state

In the excited state, the hydrogens are each attached by more traditional (two-centre two-electron) covalent bonding, two on each boron. Only the boron–boron bond links the two boron atoms, and the hydrogens on one boron are twisted compared to those on the other.[2]

Production

The only known method of producing diborane(4) is the successive abstraction of hydrogen from diborane(6) using atomic fluorine.[1] The structure of diborane(4) has not been confirmed, but the results obtained by photoionization mass spectrometry are consistent with a doubly bridged structure.[1]

Several substituted derivatives of diborane(4) have been observed.[3][4]

References

  1. 1 2 3 Ruščic, B.; Schwarz, M.; Berkowitz, J. (1989). "Molecular structure and thermal stability of B
    2    H
    4     and B
    2    H+
    4     species". The Journal of Chemical Physics. AIP Publishing. 91 (8): 4576–4581. doi:10.1063/1.456745.
  2. 1 2 3 Alkorta, Ibon; Soteras, Ignacio; Elguero, José; Del Beneb, Janet E. (23 June 2011). "The boron–boron single bond in diborane(4) as a non-classical electron donor for hydrogen bonding". Physical Chemistry Chemical Physics. 13 (31): 14026–14032. doi:10.1039/C1CP20560A.
  3. ↑ Xie, Xiaochen; Haddow, Mairi F.; Mansell, Stephen M.; Norman, Nicholas C.; Russell, Christopher A. (2012). "Diborane(4) compounds with bidentate diamino groups". Dalton Transactions. 41 (7): 2140–7. doi:10.1039/C2DT11936F. PMID 22187045.
  4. ↑ Wagner, Arne; Kaifer, Elisabeth; Himmel, Hans-Jörg (2012). "Diborane(4)–metal bonding: Between hydrogen bridges and frustrated oxidative addition". Chemical Communications. 48 (43): 5277–9. doi:10.1039/C2CC31671D. PMID 22526934.
This article is issued from Wikipedia - version of the 10/16/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.