反应详情

To 3,6-dimethoxy-2-(2,4-dimethoxybenzylamino)quinoxaline (4.45 g, 12.8 mmol), 70 ml of 50% trifluoroacetic acid in dichloromethane was added at room temperature. The resulting mixture was stirred at room temperature for 18 hours and concentrated under the reduced pressure to remove the solvent. The residue was neutralized with saturated sodium bicarbonate solution and then NaCl solution was added thereto. The product was extracted with dichloromethane and the organic layer was dried over MgSO4. After concentration under the reduced pressure, the crude product was purified by SiO2 column chromatography. Extraction of the residue with a n-hexane:ethyl acetate mixture and concentration gave 2.50 g of the titled compound (yield, 95%).

1. concentrationconcentrated under the reduced pressure
2. customto remove the solvent
3. additionNaCl solution was added
4. extractionThe product was extracted with dichloromethane
5. dry with materialthe organic layer was dried over MgSO4
6. concentrationAfter concentration under the reduced pressure
7. customthe crude product was purified by SiO2 column chromatography
8. extractionExtraction of the residue with a n-hexane
9. concentrationethyl acetate mixture and concentration