Acetoacetic ester synthesis is a method to obtain ketones from alkyl halides and β-keto esters. The reaction occurs in the presence of an alkoxide base that abstracts the acidic proton of the β-keto esters. The step results in an enolate ion which is doubly stabilized. The enolate then reacts with an alkyl halide via the S_N2 process to produce an alkylated ester intermediate with a new C–C bond. The hydrolysis of the intermediate, followed by acidification, results in an alkylated β-keto acid. Under high-temperature conditions, the β-keto acid undergoes decarboxylation to form a ketone. However, if the alkylation is repeated before hydrolysis and decarboxylation steps, a disubstituted ketone is obtained.