decarboxylating

Decarboxylating refers to the process of removing a carboxyl group from a molecule and releasing carbon dioxide. The term is used in both organic chemistry and biochemistry to describe reactions in which a carboxyl moiety is eliminated as CO2, often making the reaction thermodynamically favorable because CO2 is a stable, gaseous product. In many contexts, decarboxylation proceeds when a substrate is heated or when a catalyst or enzyme lowers the required activation energy.

In organic chemistry, decarboxylation is a common transformation of carboxylic acids and their derivatives. Thermal decarboxylation can occur for simple carboxylic acids, but it is especially notable for beta-keto acids, which decarboxylate to yield ketones. Malonic ester synthesis relies on the decarboxylation of malonate derivatives to give substituted acetic acids after alkylation and hydrolysis. Some decarboxylations are used deliberately in synthesis to remove a carboxyl group and reveal a new hydrocarbon framework or to generate an active electrophile or nucleophile in situ.

Biochemically, decarboxylation is often enzyme-catalyzed. PLP-dependent decarboxylases remove carboxyl groups from amino acids to form amines, which is important in neurotransmitter production (for example, glutamate to GABA) and in various metabolic pathways. Other biological decarboxylations remove CO2 to modify metabolic intermediates or to regulate flux through pathways.

Overall, decarboxylating is a fundamental chemical and biological step that transforms carboxyl-bearing substrates by releasing CO2 and producing a range of practical products.