Pentaborane(11) is
inorganic compound
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''.
Inorgan ...
with the
chemical formula
A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as pare ...
B
5H
11. It is an obscure
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 ...
, especially relative to the heavily studied
pentaborane(9)
Pentaborane(9) is an inorganic compound with the formula . It is one of the most common boron hydride clusters, although it is a highly reactive compound. Because of its high reactivity with oxygen, it was once evaluated as rocket or jet fuel. Lik ...
(B
5H
9). With two more hydrogen atoms than ''nido''-pentaborane(9), pentaborane(11) is classified as an ''arachno''- cluster.
Synthesis
Like many boron hydride clusters, pentaborane(11) was originally obtained from the
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
diborane
Diborane(6), commonly known as diborane, is the chemical compound with the formula . It is a highly toxic, colorless, and pyrophoric gas with a repulsively sweet odor. Given its simple formula, borane is a fundamental boron compound. It has att ...
. A more systematic synthesis entails treatment of
4H9sup>− with
boron tribromide
Boron tribromide, BBr3, is a colorless, fuming liquid compound containing boron and bromine. Commercial samples usually are amber to red/brown, due to weak bromine contamination. It is decomposed by water and alcohols.
Chemical properties
Boron ...
. The Lewis acid abstracts hydride to give unstable B
4H
8, the precursor to B
5H
11:
:
4H9sup>− + BBr
3 → B
4H
8 + HBBr
3−
:2 B
4H
8 → B
5H
11 + "B
3H
5"
References
{{Hydrides by group
Boranes