In organic chemistry, a ketone is either the functional group characterized by a carbonyl group linked to two other carbon atoms or a compound that contains this functional group. A ketone can be generally represented by the formula R1(CO)R2.

Among the other oxygen-containing compounds, the fact that ketones feature a carbonyl carbon bonded to two carbon atoms distinguishes them from carboxylic acids, aldehydes, esters, and amides. The double-bonded nature of the carbonyl group distinguishes ketones from alcohols and ethers. The smallest ketone is acetone:

Ketones are named by appending -one to the stem. Eg: butanone

Oxidation of alcohol to create ketone

Ketones can be created by oxidation of secondary alcohols. The process requires a strong oxidising agent such as potassium dichromate or other reageant containing Cr(VI). The alcohol is oxidised by heating under reflux in acidified solution. For example 2-propanol is oxidised to propanone (acetone):

H3C-CH(OH)-CH3 -> H3C-CO-CH3

Two atoms of hydrogen are removed, leaving a single oxygen atom double bonded to a carbon atom.

List of selected ketones