反应详情

Into a suspension of 75 g (499 mmol) 2,5-dimethylbenzoic acid, 103 g (748 mmol) potassium carbonate in 500 mL of DMF was added dropwise 77.9 g (549 mmol) of iodomethane with stirring at ambient temperature. After addition, the suspension was stirred for additional 5 hours. The reaction mixture was then poured into water and extracted with ethyl acetate. The organic layer was washed with water and brine and dried over anhydrous sodium sulfate. All solids were removed by filtration and the filtrate was concentrated to 80 g of colorless oil as product in 97.6% yield. 1H NMR (CDCl3) (300 MHz) δ 2.7 (s, 3H), 2.8 (s, 3H), 3.95 (s, 3H), 7.45 (s 1H), 7.51 (d, 3JHCCH=7.9 Hz, 1H), 7.42 (d, 3JHCCH=7.9 Hz, 1H)

1. additionAfter addition
2. stirringthe suspension was stirred for additional 5 hours
3. extractionextracted with ethyl acetate
4. washThe organic layer was washed with water and brine
5. dry with materialdried over anhydrous sodium sulfate
6. customAll solids were removed by filtration
7. concentrationthe filtrate was concentrated to 80 g of colorless oil as product in 97.6% yield