反应详情

1,3-Dimethoxy-2-(tol-2-yl)-4-(pyrid-3-yl)-benzene 3 (3.5 g, 11.46 mmol), acetic acid (30 ml), and hydrobromic acid (48%) (15 ml) were refluxed for 24 hr. After cooling the reaction mixture, most of the reagent was removed under reduced pressure; the residual acid was removed by mixing the concentrate with sodium bicarbonate solution (5%) (100 ml). The product was extracted into ethylacetate (100 ml), washed with water (100 ml×2) and brine (100 ml), and the ethyl acetate was evaporated. The crude product was purified by silica-gel chromatography eluting with dichloromethane and acetone (0% to 10% acetone) yielding 2.8 g (90%) of 4.

1. temperatureAfter cooling the reaction mixture
2. custommost of the reagent was removed under reduced pressure
3. customthe residual acid was removed
4. additionby mixing the
5. concentrationconcentrate with sodium bicarbonate solution (5%) (100 ml)
6. extractionThe product was extracted into ethylacetate (100 ml)
7. washwashed with water (100 ml×2) and brine (100 ml)
8. customthe ethyl acetate was evaporated
9. customThe crude product was purified by silica-gel chromatography
10. washeluting with dichloromethane and acetone (0% to 10% acetone)