1-Bromo-3-(trimethylsiloxy)benzene → (3RS,4RS)-4-hydroxy-4-(3-hydroxyphenyl)-7-methoxymethyloxy-3-[4-(methoxymethyloxy)phenyl]-3-methyl-2,3-dihydro-4H-benzopyran

HRID 1859318Notes

Reaction equation

HRID 1859318 reaction equation
C[Si]([O:5][C:6]1[CH:11]=[CH:10][CH:9]=[C:8](Br)[CH:7]=1)(C)C.[Mg].[CH3:14][O:15][CH2:16][O:17][C:18]1[CH:39]=[CH:38][C:21]2[C:22](=[O:37])[C:23]([C:27]3[CH:32]=[CH:31][C:30]([O:33][CH2:34][O:35][CH3:36])=[CH:29][CH:28]=3)([CH3:26])[CH2:24][O:25][C:20]=2[CH:19]=1>O1CCCC1>[OH:37][C:22]1([C:8]2[CH:9]=[CH:10][CH:11]=[C:6]([OH:5])[CH:7]=2)[C:21]2[CH:38]=[CH:39][C:18]([O:17][CH2:16][O:15][CH3:14])=[CH:19][C:20]=2[O:25][CH2:24][C:23]1([C:27]1[CH:32]=[CH:31][C:30]([O:33][CH2:34][O:35][CH3:36])=[CH:29][CH:28]=1)[CH3:26]

Participants

5

Reactant 3

HCID 6158011-Bromo-3-(trimethylsiloxy)benzeneHCID 5462224MagnesiumHCID 154817637-Methoxymethoxy-3-(4-methoxymethoxyphenyl)-3-methylchroman-4-one

Product 1

HCID 22123575(3RS,4RS)-4-hydroxy-4-(3-hydroxyphenyl)-7-methoxymethyloxy-3-[4-(methoxymethyloxy)phenyl]-3-methyl-2,3-dihydro-4H-benzopyranYield 67%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
0 °C

Procedure

Under argon atmosphere 3-bromomagnesium phenyl trimethylsilyl ether was prepared from 3-bromophenyl trimethylsilyl ether (3 g, 12.24 mmol) and magnesium turning (300 mg, 12.34 mmol) in dry tetrahydrofuran (10 ml) and cooled to 0° C. 7-Methoxymethyloxy-3-[4-(methoxymethyloxy)phenyl]-3-methyl-2,3-dihydro-4H-benzopyran-4-one (900 mg, 2.51 mmol) dissolved in dry tetrahydrofuran (5 ml) was slowly added dropwise thereto and then refluxed for 12 hours. The reaction mixture was cooled to room temperature, quenched with water and then extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate and concentrated under reduced pressure to remove the organic solvent. The concentrate was separated by column chromatography (n-hexane:ethyl acetate=2:1) to obtain 760 mg (yield: 67%) of the title compound as a foam.

Workup

  1. additionwas slowly added dropwise
  2. temperaturerefluxed for 12 hours
  3. temperatureThe reaction mixture was cooled to room temperature
  4. customquenched with water
  5. extractionextracted with ethyl acetate
  6. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
  7. concentrationconcentrated under reduced pressure
  8. customto remove the organic solvent
  9. customThe concentrate was separated by column chromatography (n-hexane:ethyl acetate=2:1)

Sources & evidence

ORD record
ord-78a900149b83476bb73ac7e85683b9aa
Source dataset
uspto-grants-2000_11
Patent number
US06153768

Reaction notes

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