Mannich base


A Mannich base is a beta-amino-ketone, which is formed in the reaction of an amine, formaldehyde and a carbon acid. The Mannich base is an endproduct in the Mannich reaction, which is nucleophilic addition reaction of a non-enolizable aldehyde and any primary or secondary amine to produce resonance stabilized imine. The addition of a carbanion from a CH acidic compound to the imine gives the Mannich base.

Reactivity

With primary or secondary amines, Mannich bases react with additional aldehyde and carbon acid to larger adducts HN2 and N3. With multiple acidic hydrogen atoms on the carbon acid higher adducts are also possible. Ammonia can be split off in an elimination reaction to form enals and enones.