decarboxylaation

Decarboxylation is a chemical reaction that removes a carboxyl group from an organic molecule, releasing carbon dioxide (CO2). The process can occur nonenzymatically, often by heating or under acidic conditions, or enzymatically in living organisms.

In organic chemistry, decarboxylation typically reduces a carboxylate-containing substrate to a smaller molecule, with CO2 as a byproduct. Common examples include the spontaneous decarboxylation of beta-keto acids to yield ketones and CO2, and the thermal decay of malonic acid to acetic acid. Decarboxylation strategies are used in synthesis to generate reactive intermediates and in decarboxylative coupling reactions that form new bonds.

In biochemistry, decarboxylation is widespread in metabolism. Enzyme-catalyzed decarboxylations remove CO2 from substrates in catabolic pathways. The citric acid cycle converts isocitrate to α-ketoglutarate with CO2 release, and the pyruvate dehydrogenase complex converts pyruvate to acetyl-CoA with CO2 and NADH production. Amino-acid decarboxylases remove carboxyl groups from amino acids to form amines, a key step in neurotransmitter biosynthesis and in the production of biogenic amines in foods.

CO2 production in decarboxylation can influence reaction conditions, gas evolution, and equilibrium. Conditions, catalysts, and substrates determine whether decarboxylation proceeds readily. The term is commonly spelled decarboxylation; decarboxylaation is a frequent misspelling.