Preparation of 2,5-dimethyl-4-hydroxy-2,3-dihydrofuran-3-one
Abstract
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°-280° 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.
Inventors
- 👤 Karl-Heinz Ross
- 👤 Christian Dudeck
- 👤 Walter Himmele
- 👤 Rolf Lebkuecher
- 👤 Wolfgang Sauer
Bibliographic Details
Claims Analysis
Total Claims: 2References Cited (Backward Citations)
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