Aldehyde/Ketone reduction
Abstract
Carbonyl reduction refers to the conversion of a ketone or aldehyde into the corresponding alcohol by delivery of a hydride to the electrophilic carbonyl carbon.
Keywords
Carbonyl, Reduction, Primary alcohol, Secondary alcohol
Category
Aldehyde/Ketone
Mechanism
Here, the metal hydride (NaBH4 or LiAlH4) acts as a hydride donor. The hydride attacks the electrophilic carbonyl carbon, breaking the C=O bond and transferring the electron pair to the oxygen atom, which becomes an alkoxide coordinated to the metal center (boron or aluminium). Finally, the metal alkoxide is hydrolyzed during acidic aqueous workup, releasing the free alcohol and the metal hydroxide as by-product.
