Hexaborane, also called hexaborane(10) to distinguish it from hexaborane(12) (B₆H₁₂), is a

boron hydride cluster Boron hydride clusters are compounds with the formula or related anions, where x ≥ 3. Many such cluster compounds are known. Common examples are those with 5, 10, and 12 boron atoms. Although they have few practical applications, the borane hyd ...

with the formula B₆H₁₀. It is a colorless liquid that is unstable in air.

Structure

Hexaborane(10) is classified as a ''nido''-cluster. The boron atoms define a

pentagonal pyramid In geometry, a pentagonal pyramid is a Pyramid (geometry), pyramid with a pentagon base and five triangular faces, having a total of six faces. It is categorized as a Johnson solid if all of the edges are equal in length, forming Equilateral tria ...

, with four bridging hydrogen atoms and six terminal ones. The

point group In geometry, a point group is a group (mathematics), mathematical group of symmetry operations (isometry, isometries in a Euclidean space) that have a Fixed point (mathematics), fixed point in common. The Origin (mathematics), coordinate origin o ...

of the molecule is ''C''_s.

Preparation and reactions

A laboratory route begins with bromination of pentaborane(11) followed by deprotonation of the bromide to give rB₅H₇sup>−. This anionic cluster is reduced with diborane to give the neutral product: :K rB₅H₇ + 1/2 B₂H₆ → KBr + B₆H₁₀ It can also be generated by

pyrolysis Pyrolysis is a process involving the Bond cleavage, separation of covalent bonds in organic matter by thermal decomposition within an Chemically inert, inert environment without oxygen. Etymology The word ''pyrolysis'' is coined from the Gree ...

of pentaborane(11). B₆H₁₀ can be deprotonated to give ₆H₉sup>− or protonated to give ₆H₁₁sup>+. It can act as a

Lewis base A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any sp ...

towards reactive borane radicals, forming various ''conjuncto''-clusters.

References

{{Hydrides by group Boranes