Illustrated Glossary of Organic Chemistry

Reductive amination: A reaction in which an aldehyde or ketone is reacted with ammonia or an amine to produce a new alkylated amine. The reaction involves nucleophilic carbonyl addition to produce an imine intermediate, which is subsequently reduced to an amine. Note the new amine has a higher degree of substitution than the starting amine.

	+	CH3NH2	pTsOH		NaBH4
Acetone		Methylamine		N-methylpropan-2-imine Reaction intermediate		Isopropyl methyl amine Reaction product

In this reductive amination reaction example, acetone (a ketone) is reacted with methylamine (a primary amine) in the presence of p-toluenesulfonic acid (an acid catalyst) to form N-methylpropan-2-imine, an imine intermediate. This imine is then reduced with sodium borohydride to form isopropyl methyl amine (a secondary amine)