Decarbonylation
In chemistry, decarbonylation is a type of organic reaction that involves the loss of carbon monoxide (CO). It is often an undesirable reaction, since it represents a degradation. In the chemistry of metal carbonyls, decarbonylation describes a substitution process, whereby a CO ligand is replaced by another ligand. Organic chemistry In the absence of metal catalysts, decarbonylation (vs decarboxylation) is rarely observed in organic chemistry. One exception is the decarbonylation of formic acid: The reaction is induced by sulfuric acid, which functions as both a catalyst and a dehydrating agent. Via this reaction, formic acid is occasionally employed as a source of CO in the laboratory in lieu of cylinders of this toxic gas. With strong heating, formic acid and some of its derivatives may undergo decarbonylation, even without adding a catalyst. For instance, dimethylformamide () slowly decomposes to give dimethylamine and carbon monoxide when heated to its boiling point (154 °C). Some derivatives of formic acid, like formyl chloride (), undergo spontaneous decarbonylation at room temperature (or below). Reactions involving oxalyl chloride (e.g., hydrolysis, reaction with carboxylic acids, Swern oxidation, etc.) often liberate both carbon dioxide and carbon monoxide via a fragmentation process. α-Hydroxy acids, e.g. (lactic acid and