Ethylene Glycol → 3,3-(Ethylenedioxy)-4,4-dimethyl-17beta-tert-butyldimethylsilyloxy-androst-5-ene

HRID 1182874Notes

Reaction equation

HRID 1182874 reaction equation
[CH3:1][C:2]1([CH3:30])[C:19](=[O:20])[CH2:18][CH2:17][C@@:16]2([CH3:21])[C:3]1=[CH:4][CH2:5][C@@H:6]1[C@@H:15]2[CH2:14][CH2:13][C@@:11]2([CH3:12])[C@H:7]1[CH2:8][CH2:9][C@@H:10]2[O:22][Si:23]([C:26]([CH3:29])([CH3:28])[CH3:27])([CH3:25])[CH3:24].[CH2:31](O)[CH2:32][OH:33].CC1C=CC(S(O)(=O)=O)=CC=1>C1(C)C=CC=CC=1>[CH2:31]1[CH2:32][O:33][C:19]2([CH2:18][CH2:17][C@@:16]3([CH3:21])[C:3](=[CH:4][CH2:5][C@@H:6]4[C@@H:15]3[CH2:14][CH2:13][C@@:11]3([CH3:12])[C@H:7]4[CH2:8][CH2:9][C@@H:10]3[O:22][Si:23]([C:26]([CH3:29])([CH3:28])[CH3:27])([CH3:24])[CH3:25])[C:2]2([CH3:30])[CH3:1])[O:20]1

Participants

5

Reactant 3

HCID 174Ethylene GlycolHCID 6101p-Toluenesulfonic acidHCID 687291174,4-Dimethyl-17beta-tert-butyldimethylsilyloxyandrost-5-en-3-one

Product 1

HCID 687339453,3-(Ethylenedioxy)-4,4-dimethyl-17beta-tert-butyldimethylsilyloxy-androst-5-eneYield 100%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

4,4-Dimethyl-17β-tert-butyldimethylsilyloxyandrost-5-en-3-one (4.0 g) was dissolved in toluene (235 ml). Ethylene glycol (9.3 ml) and PTSA (124 mg) were added and the mixture was refluxed for 7.5 h, removing water with a Dean-Stark trap. After cooling, water was added and the mixture was extracted with EtOAc. The organic phase was washed with 5% NaHCO3, brine then dried over Na2SO4 and evaporated to dryness to give 3,3-(ethylenedioxy)-4,4-dimethyl-17β-tert-butyldimethylsilyloxy-androst-5-ene (4.4 g, 100%) which was used without purification in the next step.

Workup

  1. temperaturethe mixture was refluxed for 7.5 h
  2. customremoving water with a Dean-Stark trap
  3. temperatureAfter cooling
  4. additionwater was added
  5. extractionthe mixture was extracted with EtOAc
  6. washThe organic phase was washed with 5% NaHCO3, brine
  7. dry with materialthen dried over Na2SO4
  8. customevaporated to dryness

Sources & evidence

ORD record
ord-08a4c7bd35b7444fa5cf2e4cedc47cf3
Source dataset
uspto-grants-2014_03
Patent number
US08664210B2

Reaction notes

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