Reaktion #362863

Reaktionsgleichung

hydrochloric acid

potassium t-butoxide

estrone

→

needles

Ausbeute 76.3%

17-Methylenestra-1,3,5(10)-trien-3-ol

Ausbeute 76.3%

Lösungsmittel

dimethylsulfoxide

DMSO

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGStirring
2. 2
   workup.WAITwas continued 1 h
3. 3
   Temperaturto cool
4. 4
   Extraktionextracted three times with 400 mL aliquots of ether
5. 5
   WaschenThe combined organic extracts were washed with 350 mL of saturated sodium bicarbonate+400 mL of brine
6. 6
   Trocknendried over sodium sulfate, and flash
7. 7
   Filtrationfiltered through a 58 mm high×84 mm dia
8. 8
   WaschenProduct continued eluting with additional ether
9. 9
   SonstigeConcentration of appropriate fractions under reduced pressure and three-fold recrystallization from aqueous ethanol

Vorschrift

A suspension of methyltriphenylphosphonium bromide (100.03 g, 0.28001 mol) and potassium t-butoxide (31.42 g, 0.2800 mol) in anh. dimethylsulfoxide (DMSO, 320 mL) under argon was stirred in an oil bath (68-81° C.) 1 h, after which estrone (15.14 g, 55.99 mmol) in anh. DMSO (320 mL) was added via syringe. See FIG. 17. Stirring was continued 1 h and the reaction allowed to cool. The mixture was poured into 800 mL of ice-1 N hydrochloric acid and then extracted three times with 400 mL aliquots of ether. The combined organic extracts were washed with 350 mL of saturated sodium bicarbonate+400 mL of brine, dried over sodium sulfate, and flash filtered through a 58 mm high×84 mm dia. column of silica gel (200-40 mesh). Product continued eluting with additional ether. Concentration of appropriate fractions under reduced pressure and three-fold recrystallization from aqueous ethanol gave very fine white needles (11.47 g, 42.73 mmol, 76%), m.p. 134-136° C., homogeneous to TLC (20% ethyl acetate/hexanes on silica gel, Rf 0.45).

Quelle