Hydrogen Bromide → 2-(Tol-2-yl)-4-(Pyrid-3-yl)-1,3-Dihydroxybenzene

Participants

Reaction Steps

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.

Provenance & Evidence