تفاعل #320818

معادلة التفاعل

water

bromoacetaldehyde diethylacetal

NaH

17β-(3-furyl)-5β-androstane-3β,14β-diol

→

3β-(2,2-diethoxy-ethoxy)-17β-(3-furyl)-5β-androstan-14β-ol

المذيبات

tetrahydrofuran

ظروف التفاعل

المعالجة

1. 1
   workup.ADDITIONwere added at room temperature in a nitrogen atmosphere
2. 2
   درجة الحرارةat reflux for 6 hrs
3. 3
   درجة الحرارةat reflux temperature for 4 hrs
4. 4
   workup.DISTILLATIONthe tetrahydrofuran was distilled under reduced pressure
5. 5
   استخلاصThe residue was extracted with methylene chloride
6. 6
   تجفيفthe organic layer was dried over anhydrous sodium sulfate
7. 7
   أخرىevaporated to dryness under reduced pressure
8. 8
   أخرىThe crude product was purified by flash-chromatography (SiO2)

الإجراء التجريبي

To a suspension of 5.5 g of NaH (60% dispersion in mineral oil) in 400 ml of dry tetrahydrofuran 7.0 g of 17β-(3-furyl)-5β-androstane-3β,14β-diol (II-a: Ref. comp.) (Minato H. and Nagasaki T., J. Chem. Soc.(C), 1966, 377) were added at room temperature in a nitrogen atmosphere. The mixture was kept at reflux for 6 hrs, then 26 ml of bromoacetaldehyde diethylacetal were added; the suspension was kept at reflux temperature for 4 hrs, 50 ml of water were added cautiously, and the tetrahydrofuran was distilled under reduced pressure. The residue was extracted with methylene chloride, the organic layer was dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. The crude product was purified by flash-chromatography (SiO2) using n-hexane/ethyl acetate 80/20 as eluant to give 6.9 g of 3β-(2,2-diethoxy-ethoxy)-17β-(3-furyl)-5β-androstan-14β-ol, as a dense oil.

المصدر