Editing Carboxylic acid (section)

===Specialized reactions===
* As with all carbonyl compounds, the protons on the [[alpha-carbon|α-carbon]] are labile due to [[keto–enol tautomerism|keto–enol tautomerization]]. Thus, the α-carbon is easily halogenated in the [[Hell–Volhard–Zelinsky halogenation]].
* The [[Schmidt reaction]] converts carboxylic acids to [[amine]]s.
* Carboxylic acids are decarboxylated in the [[Hunsdiecker reaction]].
* The [[Dakin–West reaction]] converts an amino acid to the corresponding amino ketone.
* In the [[Barbier–Wieland degradation]], a carboxylic acid on an aliphatic chain having a simple [[methylene bridge]] at the alpha position can have the chain shortened by one carbon. The inverse procedure is the [[Arndt–Eistert synthesis]], where an acid is converted into acyl halide, which is then reacted with [[diazomethane]] to give one additional methylene in the aliphatic chain.
* Many acids undergo [[oxidative decarboxylation]]. [[Enzyme]]s that catalyze these reactions are known as [[carboxylase]]s ([[Enzyme Commission number|EC]]&nbsp;6.4.1) and [[decarboxylase]]s (EC&nbsp;4.1.1).
* Carboxylic acids are reduced to [[aldehyde]]s via the [[ester]] and [[Diisobutylaluminium hydride|DIBAL]], via the acid chloride in the [[Rosenmund reduction]] and via the thioester in the [[Fukuyama reduction]].
* In [[ketonic decarboxylation]] carboxylic acids are converted to ketones.
* Organolithium reagents (>2 equiv) react with carboxylic acids to give a dilithium 1,1-diolate, a stable [[tetrahedral intermediate]] which decomposes to give a ketone upon acidic workup.
* The [[Kolbe electrolysis]] is an electrolytic, decarboxylative dimerization reaction. It gets rid of the carboxyl groups of two acid molecules, and joins the remaining fragments together.