The aldol reaction is a powerful means of forming carbon–carbon bonds in organic chemistry

Organic chemistry

Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation of carbon-based compounds, hydrocarbons, and their derivatives...

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Discovered independently by Charles-Adolphe Wurtz

Charles-Adolphe Wurtz

Adolphe Wurtz was an Alsatian French chemist. He is best remembered for his decades-long advocacy for the atomic theory and for ideas about the structures of chemical compounds, against the skeptical opinions of chemists such as Marcellin Berthelot and Etienne Henri Sainte-Claire Deville...

 and Alexander Porfyrevich Borodin in 1872, the reaction combines two carbonyl

Carbonyl

In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom: C=O. It is common to several classes of organic compounds, as part of many larger functional groups....

 compounds (the original experiments used aldehyde

Aldehyde

An aldehyde is an organic compound containing a formyl group. This functional group, with the structure R-CHO, consists of a carbonyl center bonded to hydrogen and an R group....

s) to form a new β-hydroxy carbonyl

Hydroxy ketone

A hydroxy ketone in organic chemistry is a functional group consisting of a ketone flanked by a hydroxyl group. In the two main classes the hydroxyl group can be placed in the alpha position or in the beta position .* An alpha-hydroxy ketone is called an acyloin* Prominent beta-hydroxy ketones...

 compound. These products are known as aldols, from the aldehyde + alcohol, a structural motif seen in many of the products. Aldol structural units are found in many important molecules, whether naturally occurring or synthetic.
For example, the aldol reaction has been used in the large-scale production of the commodity chemical pentaerythritol

Pentaerythritol

Pentaerythritol is the organic compound with the formula C5H12O4. This white, crystalline polyol with the neopentane backbone is a versatile building block for the preparation of many polyfunctionalized compounds such as the explosive PETN and pentaerythritol tetraacrylate...

and the synthesis of the heart disease drug Lipitor (atorvastatin

Atorvastatin

Atorvastatin , sold by Pfizer under the trade name Lipitor, is a member of the drug class known as statins, used for lowering blood cholesterol. It also stabilizes plaque and prevents strokes through anti-inflammatory and other mechanisms...

).

The aldol reaction is powerful because it unites two relatively simple molecules into a more complex one.