Tags: Chemical Compound, Chemical Substance.
Lactide is the cyclic di-ester of lactic acid i.e. 2-hydroxypropionic acid. Lactic acid cannot form a lactone as other hydroxy acids do because the hydroxy group is too close to the carboxylic group. Instead lactic acid first forms a dimer which is similar to a 5-hydroxyacid. The dimer contains a hydroxy group at a convenient distance from the carboxylic group for the formation of a lactone. Indeed the dimer readily forms a six-membered cyclic diester known as lactide.
