Dekaroksüleerumised

Dekaroksüleerumised, also known as decarboxylations, are chemical reactions that remove a carboxyl group (−COOH) from a molecule and release it as carbon dioxide (CO2). This process is fundamental in organic chemistry and biochemistry, playing a crucial role in various metabolic pathways and synthetic procedures.

In organic synthesis, decarboxylation can be achieved through several methods. Thermal decarboxylation involves heating a carboxylic acid, often in the presence of catalysts like copper or palladium, to break the carbon-carbon bond adjacent to the carboxyl group. Beta-keto acids are particularly prone to thermal decarboxylation, yielding a ketone and carbon dioxide. Another common method is oxidative decarboxylation, where the carboxyl group is oxidized and subsequently eliminated as CO2. Electrochemical decarboxylation is also employed, utilizing an electric current to drive the reaction.

Biochemically, decarboxylation is a vital process. For instance, the citric acid cycle, a central metabolic pathway, involves several decarboxylation steps that release carbon dioxide as cells break down glucose for energy. Amino acid metabolism also features decarboxylation reactions, often catalyzed by enzymes called decarboxylases, which can produce biologically active amines. For example, the decarboxylation of histidine produces histamine, a neurotransmitter and mediator of immune responses.

The study of decarboxylation is important for understanding energy production in living organisms and for developing new synthetic routes for valuable organic compounds.