反应详情

A solution of 4-bromo-6-phenylpyridazin-3-amine (1.2 g, 4.8 mmol), 2-chloro-1,1-diethoxyethane (0.884 g, 5.74 mmol), PTSA (1.09 g, 5.74 mmol) in isopropanol (25 mL) was heated to 80° C. for 40 h. After cooling to room temperature, the solution was concentrated in vacuo. The resulting mixture was treated with a saturated aq. NaHCO3 solution (50 mL), extracted with dichloromethane (50 mL×3), dried over Na2SO4, filtered and concentrated. The residue was purified by chromatography (silica gel, 200-300 mesh, petroleum ether:ethyl acetate=3:1) to give 8-bromo-6-phenylimidazo[1,2-b]pyridazine (0.6 g, 46%) as a white solid. LC-MS: [M+H]+, 274.0, tR=1.541 min.

1. concentrationthe solution was concentrated in vacuo
2. additionThe resulting mixture was treated with a saturated aq. NaHCO3 solution (50 mL)
3. extractionextracted with dichloromethane (50 mL×3)
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue was purified by chromatography (silica gel, 200-300 mesh, petroleum ether:ethyl acetate=3:1)