Dimethyl Sulfate → 3-Bromo-4-methoxybenzaldehyde

5-Bromosalicylaldehyde (25 g, 124 mmol) was dissolved in acetone (300 ml) and anhydrous potassium carbonate (17.2 g, 124 nmmol) was added. The mixture was heated and dimethyl sulfate (15.7 g, 124 mmol) was dropwise added over 45 min with gentle reflux. After the dropwise addition, the mixture was refluxed for 1 hr and cooled. Acetone was evaporated under reduced pressure. Toluene and water were added to the residue and the toluene layer was separated. The aqueous layer was extracted with toluene. The combined organic layer was washed with water and dried over anhydrous sodium sulfate. The desiccant was filtered off and the filtrate was concentrated under reduced pressure to give the objective compound (27.3 g, quantitative) as colorless crystals.

1. temperatureThe mixture was heated
2. additionAfter the dropwise addition
3. temperaturethe mixture was refluxed for 1 hr
4. temperaturecooled
5. customAcetone was evaporated under reduced pressure
6. additionToluene and water were added to the residue
7. customthe toluene layer was separated
8. extractionThe aqueous layer was extracted with toluene
9. washThe combined organic layer was washed with water
10. dry with materialdried over anhydrous sodium sulfate
11. filtrationThe desiccant was filtered off
12. concentrationthe filtrate was concentrated under reduced pressure
13. customto give the objective compound (27.3 g, quantitative) as colorless crystals

ORD record

ord-c35f36e0a67940b089bd0d79c97ea64a

Source dataset

uspto-grants-2002_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06348474B1