Benzyl Bromide → HCID 10787419, compound

Benzyl bromide (4.5 g, 38 mmol) was added under argon atmosphere at 0° C. to a suspension of 2-ethoxy-β-estradiol (2) (4.5 g, 13 mmol) and potassium carbonate (8.6 g, 62 mmol) in anhydrous ethanol (100 mL). The resulting mixture was stirred at reflux for 7.5 h. The solvent was evaporated under reduced pressure, the residue was diluted with water, and the mixture was extracted with ethyl acetate (3×200 mL). The combined organic extract was washed with water (100 mL), sodium bicarbonate (120 mL), brine (100 mL) and dried over sodium sulfate. Evaporation of the ethyl acetate under reduced pressure gave a viscous oil containing (17), which was used without further purification. Activated MnO2 (3 g) was added under an arcon atmosphere to a solution of crude alcohol (17) (1.6 g, 3.9 mmol) in anhydrous dichloromethane (50 mL). After 7 h, an additional amount of MnO2 (5 g) was added and the reaction mixture was left over night at room temperature. MnO2 (4 g) was added again and stirring was continued for 7 h. The mixture was filtered through a celite pad and the filtrate was evaporated under reduced pressure to give crude product, which was purified by column chromatography on silica gel using hexane, followed by hexane-CH2C2 (2:8) to afford pure ketone (18) (0.42 g, 8%): IR (neat) 3065, 2929, 2869, 2825, 1727, 1607, 1504, 1450 cm-1 ; 1H NMR (CDCl3) δ 0.92 (s, 3 H), 1.30-2.60 (m, 16 H), 2.83 (m, 2 H), 4.07 (q, J=8.5 Hz, 2 H), 5.10 (s, 2 H), 6.68 (s, 1 H), 6.88 (s, 1 H), 7.20-7.60 (m, 5 H).

1. temperatureat reflux for 7.5 h
2. customThe solvent was evaporated under reduced pressure
3. additionthe residue was diluted with water
4. extractionthe mixture was extracted with ethyl acetate (3×200 mL)
5. extractionThe combined organic extract
6. washwas washed with water (100 mL), sodium bicarbonate (120 mL), brine (100 mL)
7. dry with materialdried over sodium sulfate
8. customEvaporation of the ethyl acetate under reduced pressure
9. customgave a viscous oil
10. customwas used without further purification
11. waitthe reaction mixture was left over night at room temperature
12. stirringstirring
13. waitwas continued for 7 h
14. filtrationThe mixture was filtered through a celite pad
15. customthe filtrate was evaporated under reduced pressure
16. customto give crude product, which
17. customwas purified by column chromatography on silica gel

ORD record

ord-ce3c02dbd4a7481e898137cb227b1012

Source dataset

uspto-grants-2000_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06136992