Acetolactone (α-acetolactone) is an organic compound with formula . It is the smallest member of the lactone family but can also be described as the epoxide of ethenone. The compound was described in 1997 as a transient species in mass spectrometry experiments.[1]
Although acetolactone itself has not been isolated in bulk, the related species bis(trifluoromethyl)acetolactone (which has increased electronic stabilisation due to its two trifluoromethyl groups, is known and has a half-life of 8 hours at 25 °C. This compound is prepared by photolysis of bis(trifluoromethyl)malonyl peroxide.[2]