Water → 1-Methyl-7-methoxy-2-tetralone

Dihydro-7-methoxy-4-methylnapthalene (20.87 g) was dissolved in isopropanol (100 ml) and cooled in an ice bath. Monoperoxyphthalic acid magnesium salt (mmpp) (17 g) was added, then water (50 ml) was added and the mixture was stirred at room temperature for 2 hours. When oxidation was complete, the product mixture was hydrolyzed with aqueous NaHCO3, partially evaporated and extracted with ethylacetate. The latter extract was washed with brine and evaporated. The residue was dissolved in a mixture of ethanol (156 ml), water (121 ml) and conc. H2SO4 (24.3 ml), and heated to reflux under N2 atmosphere for 3 hours, cooled and neutralized with NaHCO3. After partial evaporation, the residue was extracted with ethylacetate, washed with brine, dried over MgSO4 and evaporated. The product was purified on a silica gel column using a mixture of hexanes and ethylacetate (100:1, 50:1, 50:1.5). The yield of the product was 16.2 g (71%).

1. temperaturecooled in an ice bath
2. custompartially evaporated
3. extractionextracted with ethylacetate
4. extractionThe latter extract
5. washwas washed with brine
6. customevaporated
7. dissolutionThe residue was dissolved in a mixture of ethanol (156 ml), water (121 ml) and conc. H2SO4 (24.3 ml)
8. temperatureheated
9. temperatureto reflux under N2 atmosphere for 3 hours
10. temperaturecooled
11. customAfter partial evaporation
12. extractionthe residue was extracted with ethylacetate
13. washwashed with brine
14. dry with materialdried over MgSO4
15. customevaporated
16. customThe product was purified on a silica gel column
17. additiona mixture of hexanes and ethylacetate (100:1, 50:1, 50:1.5)

ORD record

ord-4006e3f535884e55bc1a1a3f63220aaf

Source dataset

uspto-grants-1999_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05990104