[Products Name] Lithium Aluminium Hydride
[Molecular Formula] LiAlH4
[CAS No.] 16853-85-3
[Product Description]
Lithium aluminium hydride (LiAlH4), commonly abbreviated to LAH, is a reducing agent used in organic synthesis.
It is more powerful than the related reagent sodium borohydride due to the weaker Al-H bond compared to the B-H bond. Often supported by diethyl ether, It will convert esters, carboxylic acids, and ketones into the corresponding alcohols; and amide, nitro, nitrile, imine, oxime, and azide compounds into the amines. It and similar hydrides can also be used to reduce quaternary ammonium cations into the corresponding tertiary amines.
[Properties]
mp 125 °C (dec.)(lit.)
bp 0°C
density 0.97 g/mL at 20 °C
Fp 99 °F
storage temp. 2-8°C
form tablets (~0.5 g each)
Water Solubility Reacts
Sensitive Air & Moisture Sensitive
Merck 14,349
[Application]
Lithium aluminium hydride is widely used in organic chemistry as a reducing agent.
LAH is most commonly used for the reduction of esters and carboxylic acids to primary alcohols; prior to the advent of LiAlH4 this was a difficult conversion involving sodium metal in boiling ethanol (the Bouveault-Blanc reduction).
Partial reduction of acid chlorides to give the corresponding aldehyde product cannot proceed via LAH, since the latter reduces all the way to the primary alcohol. Instead, the milder lithium aluminium tri(t-butoxy)hydride must be used, which reacts significantly faster with the acid chloride than with the aldehyde.
