反应 #50340

反应方程式

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

→

title compound

11β-Hydroxyandrost-4-ene-3,17-dione

溶剂

THF

反应条件

后处理

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

实验过程

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).

来源