2-Chloro-4-hydroxybenzoic acid contains a carboxyl unit and a phenolic hydroxyl group in its chemical structure, exhibiting strong acidity. Literature reports that this carboxyl group and phenolic hydroxyl unit can undergo nucleophilic substitution reactions with iodomethane compounds under alkaline conditions, as well as esterification and etherification reactions. 2-Chloro-4-hydroxybenzoic acid is mainly used as an intermediate in organic synthesis and a basic reagent in pharmaceutical chemistry. Due to the chemical transformation activity of the carboxyl unit and phenolic hydroxyl group, some literature reports that this substance can be used for the structural modification and synthesis of antidiuretic hormone.
