21-Bromo-3alpha-hydroxy-5alpha-pregnane-11,20-dione → 21-Bromo-5alpha-pregnane-3,11,20-trione

HRID 1077023Notes

Reaction equation

HRID 1077023 reaction equation
[Br:1][CH2:2][C:3](=[O:25])[C@@H:4]1[C@:21]2([CH3:22])[C@H:7]([C@H:8]3[C@H:18]([C:19](=[O:23])[CH2:20]2)[C@:16]2([CH3:17])[C@H:11]([CH2:12][C@H:13]([OH:24])[CH2:14][CH2:15]2)[CH2:10][CH2:9]3)[CH2:6][CH2:5]1.CC(C)=O.OS(O)(=O)=O.O=[Cr](=O)=O>CC(C)=O>[Br:1][CH2:2][C:3](=[O:25])[C@@H:4]1[C@:21]2([CH3:22])[C@H:7]([C@H:8]3[C@H:18]([C:19](=[O:23])[CH2:20]2)[C@:16]2([CH3:17])[C@H:11]([CH2:12][C:13](=[O:24])[CH2:14][CH2:15]2)[CH2:10][CH2:9]3)[CH2:6][CH2:5]1

Participants

4

Reactant 2

HCID 8673346721-Bromo-3alpha-hydroxy-5alpha-pregnane-11,20-dioneHCID 131709961Jones' reagent

Product 1

HCID 8673347421-Bromo-5alpha-pregnane-3,11,20-trioneYield 85.4%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

21-Bromo-3α-hydroxy-5α-pregnane-11,20-dione (412 mg.) in acetone (20 ml) was stirred during dropwise addition of Jones reagent (0.4 ml) at room temperature. After 10 minutes, the reaction mixture was poured onto water extracted with chloroform and the combined chloroform extract was washed with water, dried (MgSO4) and evaporated. The residue was crystallised from ether/petrol to give title compound (350 mg) as white microcrystals 170°, [α]D + 132° (c 1.1).

Workup

  1. additionthe reaction mixture was poured onto water
  2. extractionextracted with chloroform
  3. extractionthe combined chloroform extract
  4. washwas washed with water
  5. dry with materialdried (MgSO4)
  6. customevaporated
  7. customThe residue was crystallised from ether/petrol

Sources & evidence

ORD record
ord-95b781a7d09e4e778756b47f6166412c
Source dataset
uspto-grants-1976_05
Patent number
US03959260

Reaction notes

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