7 Aluminium Hydride Uses : Facts You Should Know!

Aluminium hydride (AlH3) is colourless and does not vaporize immediately. Let us discuss more about this inorganic compound in a bit more detail.

The uses of Aluminium hydride are listed below-

  • Reducing agent
  • Hydroalumination
  • Carbolalumination
  • Storage of hydrogen
  • Pyrotechnic compositions
  • Complex formation

With the help of detailed explanations, reactions and examples, we will look into some of the major uses of aluminium hydride.

Reducing agent

  • Aluminium hydride (AlH3) is widely used in the reduction of various functional groups such as aldehydes (CHO), ketones (C=O), the carboxylic acid(COOH), esters etc, to their respective ethanol (OH) groups. 
  • AlH3, along with its few derivatives, helps in the synthesis of an organic compound by acting as a reducing agents.
  • The compound AlH3 which are formed are used as a solution in laboratories and industries.
  • The reduction of organohalides is a comparatively slow reaction. The reduction of an ester only takes place if there AlH3.
organohallides f
Reduction of organohalides.
ester f
Reduction of an ester
acetals f
Reduction of acetals

Hydroalumination

  • AlH3 has the property of forming C-Al bonds.
  • AlH3 helps in forming trialkyl aluminum derivatives by reacting with various alkenes. Various other agents which help in the hydroalumination process, such as Dialkylaluminum hydrides.
  • The catalysts which are used in the hydroalumination reactions are titanium or zirconium.
  • There is a slight chance of the occurrence of dehydroalumination, which results in alkene formation by alkylation.
hydro f
Hydroalumination

Carbolalumination

In Carboalumination, Aluminium hydride helps in forming a C-Al bond. In the carboalumination reaction, titanium or zirconium are used as catalysts. On the other hand, if asymmetric catalysts are used, they help in enantioselection. 

Storage of hydrogen

  • AlH3 has a strong capacity of holding 10% hydrogen by weight.
  • AlH3 can also store 148g/L density of hydrogen, which is nearly equal to twice the density of liquid hydrogen. 
  • AlH3 also helps in power generation in an efficient way.

Pyrotechnic compositions

Aluminium hydride is used to prepare the substances which produce an effect by light, sound and smoke with the help of self-sustaining exothermic reactions.

Complex formation

Aluminium hydride tends to form complexes, especially with lewis bases.

Conclusion

Aluminium hydride is used for various organic chemical synthesis and reduction processes. The IUPAC name of aluminium hydride is alumane. It also reacts with a few oxidizers. If it is exposed to heat for some time, it shows characteristics of a decomposition reaction.