反応 #50340

反応方程式

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

→

title compound

11β-Hydroxyandrost-4-ene-3,17-dione

溶媒

THF

反応条件

後処理

1. 1
   その他degassed
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
   洗浄for rinse purposes
4. 4
   温度is slowly heated to 50°
5. 5
   その他The 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
   その他The unreacted zinc is removed by filtration
8. 8
   洗浄is washed with aqueous ethyl acetate
9. 9
   洗浄The combined filtrate and wash
10. 10
    その他to separate
11. 11
    洗浄The organic layer is washed with water (3×25 ml)
12. 12
    濃縮finally is concentrated under vacuum to a residue
13. 13
    その他The residue is recrystallized from 1 part toluene and 2 parts heptane

実験手順

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).

出典