Sodium hydride → 1alpha,3beta-Bis(tert-butyldimethylsilyloxy)-17-(tert-butoxycarbonylmethoxymethyl)androsta-5,7,16-triene

HRID 1792207Notes

Reaction equation

HRID 1792207 reaction equation
[Si:1]([O:8][C@@H:9]1[C@@:26]2([CH3:27])[C:13](=[CH:14][CH:15]=[C:16]3[C@@H:25]2[CH2:24][CH2:23][C@@:21]2([CH3:22])[C@H:17]3[CH2:18][CH:19]=[C:20]2[CH2:28][OH:29])[CH2:12][C@@H:11]([O:30][Si:31]([C:34]([CH3:37])([CH3:36])[CH3:35])([CH3:33])[CH3:32])[CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].[H-].[Na+].C1OCCOCCOCCOCCOC1.Br[CH2:56][C:57]([O:59][C:60]([CH3:63])([CH3:62])[CH3:61])=[O:58]>O1CCCC1.C(OCC)(=O)C>[Si:1]([O:8][C@@H:9]1[C@@:26]2([CH3:27])[C:13](=[CH:14][CH:15]=[C:16]3[C@@H:25]2[CH2:24][CH2:23][C@@:21]2([CH3:22])[C@H:17]3[CH2:18][CH:19]=[C:20]2[CH2:28][O:29][CH2:56][C:57]([O:59][C:60]([CH3:63])([CH3:62])[CH3:61])=[O:58])[CH2:12][C@@H:11]([O:30][Si:31]([C:34]([CH3:37])([CH3:36])[CH3:35])([CH3:32])[CH3:33])[CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2]

Participants

7

Reactant 4

HCID 24758Sodium hydrideHCID 3633615-Crown-5HCID 79177tert-Butyl bromoacetateHCID 673014381alpha,3beta-Bis(tert-butyldimethylsilyloxy)-17-(hydroxymethyl)androsta-5,7,16-triene

Product 1

HCID 673017221alpha,3beta-Bis(tert-butyldimethylsilyloxy)-17-(tert-butoxycarbonylmethoxymethyl)androsta-5,7,16-trieneYield 78.1%

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolventHCID 8857Ethyl AcetateSolvent

Procedure

A solution of 1α,3β-bis(tert-butyldimethylsilyloxy)-17-(hydroxymethyl)androsta-5,7,16-triene (1.0 g, 1.84 mmol), sodium hydride (60% in oil, 220 mg, 5.50 mmol), 15-crown-5 (400 mg, 1.82 mmol) and t-butyl bromoacetate (0.55 ml, 3.69 mmol) in tetrahydrofuran (20 ml) was refluxed under heating for 1 hour and 15 min. The reaction solution was diluted with ethyl acetate and filtered with CELITE. Under cooling with ice, water was added dropwise to the filtrate which was then washed with saturated brine. The organic layer was dried over anhydrous magnesium sulfate, evaporated under reduced pressure to remove the solvent and the thus obtained residue was purified by column chromatography (hexane:ethyl acetate=20:1) to give the titled compound (946.6 mg, 78%) as a colorless oil.

Workup

  1. temperatureunder heating for 1 hour and 15 min
  2. filtrationfiltered with CELITE
  3. temperatureUnder cooling with ice, water
  4. additionwas added dropwise to the filtrate which
  5. washwas then washed with saturated brine
  6. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
  7. customevaporated under reduced pressure
  8. customto remove the solvent
  9. customthe thus obtained residue was purified by column chromatography (hexane:ethyl acetate=20:1)

Sources & evidence

ORD record
ord-8eca95401ac24e66a48eeaee52e9b4de
Source dataset
uspto-grants-2006_07
Patent number
US07074777B2

Reaction notes

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