Pentaborane(11) is
inorganic compound
In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemist ...
with the
chemical formula
In chemistry, 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, ...
B
5H
11. It is an obscure
boron hydride cluster, especially relative to the heavily studied
pentaborane(9)
Pentaborane(9) is an inorganic compound with the formula B5H9. It is one of the most common boron hydride clusters, although it is a highly reactive compound. Because of its high reactivity toward oxygen, it was once evaluated as rocket or jet fue ...
(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
The pyrolysis (or devolatilization) process is the thermal decomposition of materials at elevated temperatures, often in an inert atmosphere. It involves a change of chemical composition. The word is coined from the Greek-derived elements ''py ...
of
diborane
Diborane(6), generally known as diborane, is the chemical compound with the formula B2H6. It is a toxic, colorless, and pyrophoric gas with a repulsively sweet odor. Diborane is a key boron compound with a variety of applications. It has attracte ...
. 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