Reaktion #60576
ord-f29323239000469cbfcf960cb7b57b7e
Reaktionsgleichung
2-methoxy-estra-1,3,5(10)-triene-3,17β-diol
diethylamino sulfur trifluoride
→
17α-fluoro-3-hydroxy-2-methoxy-estra-1,3,5(10)-triene
Ausbeute 21.0%
Reagenzien
Keine
Lösungsmittel
Reaktionsbedingungen
Temperatur
-35°CELSIUS
Detaillierte Bedingungen
See reaction.notes.procedure_details.
Aufarbeitung
- 1Sonstigethe cold bath was removed
- 2workup.ADDITIONit was poured into aqueous sodium bicarbonate solution
- 3Extraktionextracted with dichloromethane (3×)
- 4SonstigeThe combined organic phases were dried
- 5Einengenconcentrated by evaporation in a rotary evaporator
- 6SonstigeFlash chromatography (cyclohexane/ethyl acetate=10:1) yielded 49% crude product, which
- 7Sonstigewas purified by means of HPLC (Chiracel OD-H 250×4.6 mm; n-heptane/2-propanol=95/5)
Vorschrift
215 mg of 2-methoxy-estra-1,3,5(10)-triene-3,17β-diol was dissolved in 20 ml of absolute dichloromethane and cooled to −35° C. Then, 280 μl of diethylamino sulfur trifluoride was added, and the cold bath was removed. After 1 hour, it was poured into aqueous sodium bicarbonate solution and extracted with dichloromethane (3×). The combined organic phases were dried and concentrated by evaporation in a rotary evaporator. Flash chromatography (cyclohexane/ethyl acetate=10:1) yielded 49% crude product, which was purified by means of HPLC (Chiracel OD-H 250×4.6 mm; n-heptane/2-propanol=95/5). 46 mg (21%) of 17α-fluoro-3-hydroxy-2-methoxy-estra-1,3,5(10)-triene was obtained as colorless crystals.