Imidazole → HCID 69989451, compound

HRID 481134Notes

Reaction equation

HRID 481134 reaction equation
[CH3:1][O:2][C:3](=[O:27])[CH2:4][C@@H:5]1[C@:22]2([CH3:23])[C:8]([C:9]3[CH2:10][CH2:11][CH:12]4[C@:17]([C:19]=3[CH2:20][CH2:21]2)([CH3:18])[CH2:16][CH2:15][C@H:14]([OH:24])[C:13]4([CH3:26])[CH3:25])=[CH:7][CH2:6]1.[Si:28](Cl)([C:31]([CH3:34])([CH3:33])[CH3:32])([CH3:30])[CH3:29].N1C=CN=C1>CN(C)C=O>[CH3:1][O:2][C:3](=[O:27])[CH2:4][C@@H:5]1[C@:22]2([CH3:23])[C:8]([C:9]3[CH2:10][CH2:11][CH:12]4[C@:17]([C:19]=3[CH2:20][CH2:21]2)([CH3:18])[CH2:16][CH2:15][C@H:14]([O:24][Si:28]([CH3:30])([CH3:29])[C:31]([CH3:34])([CH3:33])[CH3:32])[C:13]4([CH3:26])[CH3:25])=[CH:7][CH2:6]1

Participants

5

Reactant 3

HCID 795ImidazoleHCID 28928tert-Butyldimethylsilyl chlorideHCID 69989933HCID 69989933, compound

Product 1

HCID 69989451HCID 69989451, compoundYield 103.8%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

92 g of 4,4-dimethyl-3β-hydroxypregna-8,14-dien-21-oic acid methyl ester is stirred with 0.75 liter of N,N-dimethylformamide, 51 g of tert-butyldimethylsilyl chloride and 27.8 g of imidazole for 18 hours at 70° C. After cooling, it is poured into 10 liters of an ice-cold 0.5 molar aqueous hydrochloric acid and filtered. The filter cake is taken up in ethyl acetate, washed neutral with 1N sodium hydroxide solution, dried on sodium sulfate, filtered and concentrated by evaporation. 124.8 g of 4,4-dimethyl-3β-[[dimethyl(1,1-dimethylethyl)silyl]oxy]pregna-8,14-dien-21-oic acid methyl ester is obtained, which is further used without purification.

Workup

  1. temperatureAfter cooling
  2. filtrationfiltered
  3. washwashed neutral with 1N sodium hydroxide solution
  4. customdried on sodium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated by evaporation

Sources & evidence

ORD record
ord-e7aeb382de1648ae87cc1e7cc726fc51
Source dataset
uspto-grants-2003_11
Patent number
US06653491B1

Reaction notes

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