Preparation of 2,5-dimethyl-4-hydroxy-2,3-dihydrofuran-3-one

US4290960A · kind A · utility

Assignee

• BASF SE

Inventors

• Karl-Heinz Ross · Grünstadt, DE
• Christian Dudeck
• Walter Himmele · Monsheim, DE
• Rolf Lebkuecher · Ludwigshafen, DE
• Wolfgang Sauer · Everberg, BE

Key dates

• Filing date: Mar 5, 1980
• Grant date: Sep 22, 1981
• Expiry date: Mar 5, 2000

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D307/60
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the preparation of the sought-after scent 2,5-dimethyl-4-hydroxy-2,3-dihydrofuran-3-one, and novel intermediates for the preparation of this compound. 2,5-Dimethyl-4-hydroxy-2,3-dihydrofuran-3-one is prepared by first epoxidizing hex-3-ene-2,5-diol in the liquid phase with hydrogen peroxide to give the novel compound 3,4-epoxy-hexane-2,5-diol, which at 40.degree.-280.degree. C. is converted, by means of a catalytic amount of an acid, to the novel compound 2,5-dimethyl-3,4-dihydroxy-tetrahydro-furan. The latter is dehydrogenated by means of oxygen over a silver catalyst or copper catalyst to give the nove compound 2,5-dimethyl-4-hydroxy-tetrahydrofuran-3-one, which is oxidized by means of bismuth oxide, in concentrated acetic acid solution, to give the desired compound 2,5-dimethyl-4-hydroxy-2,3-dihydrofuran-3-one.