The amides present acidic hydrogens of Pka = 30 on the carbon a . Deprotonation of the a position generates a resonance stabilized base, called the amide enolate.
Amide enolates are good nucleophiles and attack haloalkanes, aldehydes and ketones, esters, open epoxides...
Note that only amides fully alkylated on the nitrogen atom can form enolates. If there are acidic hydrogens in the nitrogen, amidates will be formed.
