تفاعل #487149

معادلة التفاعل

potassium t-butoxide

1α,3β-bis(t-butyldimethylsilyloxy)-17-oxoandrosta-5,7-diene

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title compound

المردود 23.1%

1α,3β-Bis(t-butyldimethylsilyloxy)-16α-hydroxy-17-oxoandrosta-5,7-diene

المردود 23.1%

المذيبات

tetrahydrofuran

tetrahydrofuran

tetrahydrofuran

ظروف التفاعل

المعالجة

1. 1
   workup.STIRRINGthe mixture was further stirred at -78° C. for 1.5 hour
2. 2
   أخرىThe reaction mixture was quenched with an aqueous saturated ammonium chloride solution
3. 3
   workup.ADDITIONpoured into water
4. 4
   استخلاصextracted with ethyl acetate
5. 5
   غسيلThe organic layer was washed with brine
6. 6
   تجفيفdried over anhydrous magnesium sulfate
7. 7
   تركيزThe mixture was concentrated under reduced pressure
8. 8
   ترشيحthe deposited solids were filtered
9. 9
   تركيزthe filtrate was concentrated again
10. 10
    أخرىthe residue was purified by column chromatography on silica gel (hexane:ethyl acetate:chloroform=7:1:2)

الإجراء التجريبي

Under an argon atmosphere, a solution of potassium t-butoxide (4.13 g, 36.8 mmol) in dry tetrahydrofuran (500 ml) was cooled to -78° C., and a solution of 1α,3β-bis(t-butyldimethylsilyloxy)-17-oxoandrosta-5,7-diene (13.0 g, 24.5 mmol) in tetrahydrofuran (40 ml) was added dropwise. After the mixture was stirred at the same temperature for 1 hour, a solution of 2-(phenylsulfonyl)-3-phenyloxazyldine (9.62 g, 36.8 mmol) in tetrahydrofuran (40 ml) was added dropwise and the mixture was further stirred at -78° C. for 1.5 hour. The reaction mixture was quenched with an aqueous saturated ammonium chloride solution, poured into water and extracted with ethyl acetate. The organic layer was washed with brine and dried over anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure and the deposited solids were filtered, then the filtrate was concentrated again and the residue was purified by column chromatography on silica gel (hexane:ethyl acetate:chloroform=7:1:2) to give the title compound as a white solid (3.10 g, 23%).

المصدر