Imidazole → HCID 54232237, compound

HRID 362795Notes

Reaction equation

HRID 362795 reaction equation
N1C=CN=C1.[C:6]([O:9][CH:10]1[CH2:29][CH2:28][C@@:27]2([CH3:30])[C:12](=[CH:13][CH2:14][C@@H:15]3[C@@H:26]2[CH2:25][CH2:24][C@@:23]2([CH3:31])[C@H:16]3[CH2:17][CH2:18][C@@H:19]2[CH:20]([OH:22])[CH3:21])[CH2:11]1)(=[O:8])[CH3:7].[Si:32](Cl)([C:35]([CH3:38])([CH3:37])[CH3:36])([CH3:34])[CH3:33]>CN(C)C=O>[C:6]([O:9][CH:10]1[CH2:29][CH2:28][C@@:27]2([CH3:30])[C:12](=[CH:13][CH2:14][C@@H:15]3[C@@H:26]2[CH2:25][CH2:24][C@@:23]2([CH3:31])[C@H:16]3[CH2:17][CH2:18][C@@H:19]2[CH:20]([O:22][Si:32]([C:35]([CH3:38])([CH3:37])[CH3:36])([CH3:34])[CH3:33])[CH3:21])[CH2:11]1)(=[O:8])[CH3:7]

Participants

5

Reactant 3

HCID 795ImidazoleHCID 28928tert-Butyldimethylsilyl chlorideHCID 54019415HCID 54019415, compound2×

Product 1

HCID 54232237HCID 54232237, compound

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

Imidazole (203.7 gm, 2.28 mol) was added to a stirred suspension of 3-acetoxy-pregn-5-en-20-ol (361 gm, 1 mol, product of Step 1) in dimethylformamide (3.7 L). t-Butyldimethylsilyl chloride (228.9 mg, 1.52 mol) was added over a 10-15 min period. The mixture was stirred at room temperature for 3 days. The dimethylformamide was removed by decantation and methanol (50 mL) was added to it. Water (4 L) was added and the solution extracted with ethyl acetate (2×4 L). The precipitate remaining behind after decantation was dissolved in ethyl acetate and added to the above ethyl acetate extracts. The combined solvent extracts were washed with water, saturated salt solution, and dried over anhydrous magnesium sulfate. The solvent was removed by rotoevaporation and the product purified by column chromatography on silica gel eluted with 2:1 hexane-methylene chloride followed by 1:1 hexane-methylene chloride. The title compound was isolated as a mixture of 20α- and β-isomers.

Workup

  1. customThe dimethylformamide was removed by decantation and methanol (50 mL)
  2. additionwas added to it
  3. additionWater (4 L) was added
  4. extractionthe solution extracted with ethyl acetate (2×4 L)
  5. dissolutionwas dissolved in ethyl acetate
  6. additionadded to the above ethyl acetate extracts
  7. washThe combined solvent extracts were washed with water, saturated salt solution
  8. dry with materialdried over anhydrous magnesium sulfate
  9. customThe solvent was removed by rotoevaporation
  10. customthe product purified by column chromatography on silica gel
  11. washeluted with 2:1 hexane-methylene chloride

Sources & evidence

ORD record
ord-99e4265679ec46c8a20bc0da4a80f171
Source dataset
uspto-grants-1999_02
Patent number
US05872126

Reaction notes

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