The invention relates to a preparation method of
alkyl furanone. The preparation steps are as follows: dripping acetyl tert-
butyl acetate into absolute aether containing
sodium metal until aether reflow, maintaining
reflux after finishing dripping to obtain
mixed solution A; dripping alpha-bromo-
propionyl chloride into
mixed solution A at 12-15 DEG C, maintaining the temperature after finishing dripping, standing at
room temperature, precipitating the organic phase and washing with water, extracting the aqueous layer with aether, merging the organic phase and
drying to obtain
mixed solution B; evaporating mixed solution B out of aether, carrying out reduced pressure reaction on the residual liquid to obtain mixed solution C; and refining mixed solution C, blending with water, regulating pH value with
sodium hydroxide solution to 7.9-8, adding
hydrogen peroxide, regulating pH value of the product with
hydrochloric acid solution to 1-2, extracting with aether,
drying extract, removing aether and carrying out reduced pressure
evaporation to obtain pale yellow oil-
solid mixture, i.e. finished product of
alkyl furanone. The preparation method has short technique period, simple operation, satisfactory yield, and good color, scent and
flavor of the finished product.