Toluene → 4,4a,5,6,7,8-Hexahydro-2(3H)-naphthalenone

Toluene (300 ml) and methyl vinyl ketone (42 ml) were added to 1-(4-(1,4-dioxaspiro[4.5]decan-8-yl)cyclohex-1-enyl)pyrrolidine (105.8 g) obtained in the first step in a reaction vessel at room temperature under an atmosphere of nitrogen, and the mixture was refluxed for 6 hours. After the reaction mixture had been cooled to room temperature, sodium acetate (18 g), acetic acid (36 ml) and water (60 ml) were added, and the mixture was refluxed for 4 hours. After the reaction mixture had been cooled to room temperature, water (200 ml) was added, and then the aqueous layer was extracted with ethyl acetate. The combined organic layers were washed with brine, and dried over anhydrous magnesium sulfate. The methanol was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (eluent: ethyl acetate/n-heptane=1/5 by volume) and then by recrystallization (solvent: Solmix/n-heptane=1/9 by volume) to give 6-(1,4-dioxaspiro[4.5]decan-8-yl))-4,4a,5,6,7,8-hexahydronaphthalene-2(3H)-one (43.3 g).

1. customobtained in the first step in a reaction vessel at room temperature under an atmosphere of nitrogen
2. temperaturethe mixture was refluxed for 6 hours
3. temperaturethe mixture was refluxed for 4 hours
4. temperatureAfter the reaction mixture had been cooled to room temperature
5. extractionthe aqueous layer was extracted with ethyl acetate
6. washThe combined organic layers were washed with brine
7. dry with materialdried over anhydrous magnesium sulfate
8. distillationThe methanol was distilled off under reduced pressure
9. customThe residue was purified by silica gel column chromatography (eluent: ethyl acetate/n-heptane=1/5 by volume)
10. customby recrystallization (solvent: Solmix/n-heptane=1/9 by volume)

ORD record

ord-b009653822334d8daa425e824f821cd0

Source dataset

uspto-grants-2013_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08465674B2