Imidazole → 6-(10-Acetoxydecyl)-4-tert-butyldiphenylsilyloxy-2,3-dimethoxy-5-methylphenol

HRID 1648706Notes

Reaction equation

HRID 1648706 reaction equation
[CH3:1][O:2][C:3]1[C:4](=[O:24])[C:5]([CH2:13][CH2:14][CH2:15][CH2:16][CH2:17][CH2:18][CH2:19][CH2:20][CH2:21][CH2:22][OH:23])=[C:6]([CH3:12])[C:7](=[O:11])[C:8]=1[O:9][CH3:10].[C:25](Cl)(=[O:27])[CH3:26].S(S([O-])=O)([O-])=O.[Na+].[Na+].[C:37]([Si:41](Cl)([C:48]1[CH:53]=[CH:52][CH:51]=[CH:50][CH:49]=1)[C:42]1[CH:47]=[CH:46][CH:45]=[CH:44][CH:43]=1)([CH3:40])([CH3:39])[CH3:38].N1C=CN=C1>ClCCl.O.N1C=CC=CC=1>[C:25]([O:23][CH2:22][CH2:21][CH2:20][CH2:19][CH2:18][CH2:17][CH2:16][CH2:15][CH2:14][CH2:13][C:5]1[C:4]([OH:24])=[C:3]([O:2][CH3:1])[C:8]([O:9][CH3:10])=[C:7]([O:11][Si:41]([C:37]([CH3:40])([CH3:39])[CH3:38])([C:48]2[CH:49]=[CH:50][CH:51]=[CH:52][CH:53]=2)[C:42]2[CH:47]=[CH:46][CH:45]=[CH:44][CH:43]=2)[C:6]=1[CH3:12])(=[O:27])[CH3:26]

Participants

9

Reactant 5

HCID 795ImidazoleHCID 3686IdebenoneHCID 6367Acetyl chlorideHCID 24489Sodium DithioniteHCID 94078tert-Butyldiphenylchlorosilane

Product 1

HCID 152949946-(10-Acetoxydecyl)-4-tert-butyldiphenylsilyloxy-2,3-dimethoxy-5-methylphenol

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 1049PyridineSolventHCID 6344DichloromethaneSolvent

Procedure

2,3-Dimethoxy-6-(10-hydroxydecyl)-5-methylbenzoquinone (3.38 g, 10 mmol) was dissolved in dichloromethane (50 ml). Pyridine (1 ml) followed by acetyl chloride (0.8 ml) was added with stirring under ice-cooling, and the mixture was stirred for 1 hour. Water (5 ml) was added to the reaction mixture which was then stirred for 20 minutes. Then sodium hydrosulfite (4 g) was added, and the mixture was stirred at room temperature for 2 hours. The dichloromethane layer was separated, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was dissolved in dichloromethane (50 ml), and tert-butylchlorodiphenylsilane (5.5 g, 20 mmol) and imidazole (1.36 g, 20 mmol) were added. The mixture was stirred at 43° C. for 16 hours under a stream of nitrogen. The reaction mixture was washed with water, dried over anhydrous magnesium sulfate and concentrated under reduced pressure to obtain crude 6-(10-acetoxydecyl)-4-tert-butyldiphenylsilyloxy-2,3-dimethoxy-5-methylphenol. The concentrate was dissolved in dimethylformamide (15 ml). Sulfur trioxide-pyridine complex (3.2 g, 20 mmol) was added, and the mixture was stirred at room temperature for 5 hours. The reaction mixture was concentrated under reduced pressure. The residue was dissolved in methanol (40 ml), and 1N sodium hydroxide solution (60 ml) was added. The mixture was allowed to react for 16 hours. Methanol was distilled off under reduced pressure, and the residue was extracted with ether. The aqueous layer was subjected to Amberlite (trade mark) XAD-II column chromatography and eluted with water followed by 50% ethanol/water. The desired fraction was concentrated and lyophilized to obtain the desired compound (2.8 g).

Workup

  1. additionwas added
  2. temperaturecooling
  3. stirringthe mixture was stirred for 1 hour
  4. stirringwas then stirred for 20 minutes
  5. stirringthe mixture was stirred at room temperature for 2 hours
  6. customThe dichloromethane layer was separated
  7. dry with materialdried over anhydrous magnesium sulfate
  8. concentrationconcentrated under reduced pressure
  9. dissolutionThe residue was dissolved in dichloromethane (50 ml)
  10. stirringThe mixture was stirred at 43° C. for 16 hours under a stream of nitrogen
  11. washThe reaction mixture was washed with water
  12. dry with materialdried over anhydrous magnesium sulfate
  13. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-e930a4764a714c45b2cd7d67827ff35a
Source dataset
uspto-grants-1995_07
Patent number
US05436359

Reaction notes

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