Reactions:
Carboxylic acids and carboxylic acid derivatives generally react along with nucleophiles in a reaction known as nucleophilic substitution. The reaction includes replacement of one nucleophile with other. Nucleophilic substitution is feasible since the displaced nucleophile consist of an electronegative heteroatom (Cl, O, or N) that is capable of stabilizing a negative charge.
Figure: Nucleophilic substitution.