Process for the preparation of substituted furanones

A process for preparing substituted furanones which comprises combining a 1,2-epoxyalkane containing from 3 to 6 carbon atoms, a beta-ketoester of the formula ##STR14## where R.sub.2 is a C.sub.1-4 alkyl group and X is a C.sub.4-10 alkoxy group, and water;

• adding aqueous sodium hydroxide or potassium hydroxide with agitation at a rate such that the temperature of the reaction mixture does not exceed 40.degree. C., said reaction mixture containing 20% to 60% water and 2% to 4% molar excess of the base based on the beta-ketoester, with the molar ratio of the 1,2-epoxyalkane to beta-ketoester ranging from 1:1.1 to 1:1.7;
• maintaining the temperature of the mixture from 20.degree. C. to 35.degree. C. until the reaction is essentially complete;
• adding mineral acid to adjust the pH to between 4 and 7;
• separating the organic phase from the aqueous phase;
• and recovering a substituted furanone product of the formula ##STR15## wherein R is a C.sub.1-4 alkyl group and R.sub.2 is the same as defined above from the organic phase.