반응 #50340

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9α-Bromo-11β-hydroxyandrost-4-ene-3,17-dione

→

title compound

11β-Hydroxyandrost-4-ene-3,17-dione

용매

THF

반응 조건

후처리

1. 1
   기타degassed
2. 2
   workup.ADDITIONThis solution is added dropwise over 20 min to a freshly degassed slurry of chromic chloride hexahydrate (81 mg), thiovanic acid (0.70 ml) and zinc dust (555 mg) in DMF (4 ml) at 0° THF (about 8 ml)
3. 3
   세척for rinse purposes
4. 4
   온도is slowly heated to 50°
5. 5
   기타The THF is removed by vacuum distillation
6. 6
   workup.ADDITIONthe remaining slurry is diluted with ethyl acetate (25 ml) and water (25 ml)
7. 7
   기타The unreacted zinc is removed by filtration
8. 8
   세척is washed with aqueous ethyl acetate
9. 9
   세척The combined filtrate and wash
10. 10
    기타to separate
11. 11
    세척The organic layer is washed with water (3×25 ml)
12. 12
    농축finally is concentrated under vacuum to a residue
13. 13
    기타The residue is recrystallized from 1 part toluene and 2 parts heptane

실험 절차

9α-Bromo-11β-hydroxyandrost-4-ene-3,17-dione (I, PREPARATION 2, 2.134 g) is dissolved in THF (THF 20ml) and degassed as described in EXAMPLE 1. This solution is added dropwise over 20 min to a freshly degassed slurry of chromic chloride hexahydrate (81 mg), thiovanic acid (0.70 ml) and zinc dust (555 mg) in DMF (4 ml) at 0° THF (about 8 ml) is used for rinse purposes. The slurry is stirred at 0° to 2° for 2.2 hr and then is slowly heated to 50°. The THF is removed by vacuum distillation and the remaining slurry is diluted with ethyl acetate (25 ml) and water (25 ml). The unreacted zinc is removed by filtration and is washed with aqueous ethyl acetate. The combined filtrate and wash is allowed to separate. The organic layer is washed with water (3×25 ml) and finally is concentrated under vacuum to a residue. The residue is recrystallized from 1 part toluene and 2 parts heptane to give the title compound, TLC Rf =0.45 (methanol/methylene chloride, 5/95); HPLC 96.7% (II), 2.9% ∆9(11).

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