Ethanol → Dimedone

Temperature

45 °C

A mixture of 3-hydroxy-5,5-dimethyl-2-cyclohexen-1-one (dimedone), and R1 -thiolsulfonate, an alkali metal hydroxide, water and a water-miscible solvent, i.e., methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, dimethylformamide, dioxane or acetonitrile, is heated with stirring at any temperature between about 45°C. and the boiling temperature of the aqueous solvent (preferably at the boiling temperature) for a period of time of about one hour to about 48 hours (preferably three to 24 hours). After the reaction, the solvent mixture is removed by evaporation or by distillation. The residue is washed with water to remove the sulfinate salt by-product, and the crude product is collected on a filter and dried. Purification is accomplished by recrystallizing the crude product from an organic solvent, i.e., a hydrocarbon or lower alkanol such as benzene, cyclohexane, n-hexane, methylcyclohexane, n-pentane, ethanol, aqueous ethanol, methanol, aqueous methanol or toluene or a combination thereof.

1. waitthe boiling temperature of the aqueous solvent (preferably at the boiling temperature) for a period of time of about one hour to about 48 hours (preferably three to 24 hours)
2. customAfter the reaction
3. customthe solvent mixture is removed by evaporation or by distillation
4. washThe residue is washed with water
5. customto remove the sulfinate salt by-product
6. customthe crude product is collected on
7. filtrationa filter
8. customdried
9. customPurification
10. customby recrystallizing the crude product from an organic solvent, i.e.

ORD record

ord-daf116f38c9242cf805ee89d844d33c8

Source dataset

uspto-grants-1976_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US03943176