Methyl iodide → Isovanillin

Temperature

90 °C

3,4-Dihydroxybenzaldehyde (2.76 g, 20 mmol) was dissolved in DMF (15 ml), and methyl iodide (37.4 ml, 60 mmol) and anhydrous lithium carbonate (4.4 g, 60 mmol) were successively added to this solution. After being stirred at an external temperature of 90° C. for 1.5 hours, the reaction mixture was cooled to room temperature and the inorganic salt was filtered off. A saturated aqueous solution of ammonium chloride (200 ml) was added to the filtrate to adjust the aqueous layer to a pH of from 7 to 8, and the solution was extracted with ethyl acetate (300 ml×2). The combined organic layer was washed with a saturated aqueous solution of sodium chloride (300 ml), dried over anhydrous magnesium sulfate, filtered to remove the desiccating agent, and concentrated under reduced pressure to give the title compound (2.5 g, 82.2%) (Table 1).

1. temperaturethe reaction mixture was cooled to room temperature
2. filtrationthe inorganic salt was filtered off
3. additionA saturated aqueous solution of ammonium chloride (200 ml) was added to the filtrate
4. extractionthe solution was extracted with ethyl acetate (300 ml×2)
5. washThe combined organic layer was washed with a saturated aqueous solution of sodium chloride (300 ml)
6. dry with materialdried over anhydrous magnesium sulfate
7. filtrationfiltered
8. customto remove the desiccating agent
9. concentrationconcentrated under reduced pressure

ORD record

ord-8d389578eefe499790ef594c86dfd171

Source dataset

uspto-grants-2004_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06806276B2