反应详情

Ethyl 3-formyl-4-methoxybenzoate (500 mg) obtained in step C of Example 1-2-1 was dissolved in 10 mL of methanol. Trimethyl orthoformate (263 μL) and 41 mg of p-toluenesulfonic acid monohydrate were added to the solution, and then the mixture was heated for 2 hours under reflux. After the reaction solution was cooled, 5 mL of a saturated aqueous solution of sodium bicarbonate was added, and the resulting mixture was concentrated under reduced pressure. The residue was diluted with ethyl acetate, washed with purified water and then with a saturated aqueous solution of sodium chloride, and dried over anhydrous sodium sulfate. The anhydrous sodium sulfate was separated by filtration, whereafter the filtrate was concentrated under reduced pressure. The residue was dried under reduced pressure to obtain 596 mg (97%) of ethyl 3-dimethoxymethyl-4-methoxybenzoate.

1. temperaturethe mixture was heated for 2 hours
2. temperatureunder reflux
3. temperatureAfter the reaction solution was cooled
4. concentrationthe resulting mixture was concentrated under reduced pressure
5. additionThe residue was diluted with ethyl acetate
6. washwashed with purified water
7. dry with materialwith a saturated aqueous solution of sodium chloride, and dried over anhydrous sodium sulfate
8. customThe anhydrous sodium sulfate was separated by filtration, whereafter the filtrate
9. concentrationwas concentrated under reduced pressure
10. customThe residue was dried under reduced pressure