反应详情

To a stirred solution of 4-(5-chloro-2-methoxyphenyl)pyridazine (Preparation 6, 22 g, 100 mmol) in dichloromethane (200 mL) at 0° C. was added drop wise a solution of boron tribromide (48 mL, 499 mmol) in dichloromethane (200 mL). The reaction mixture was stirred at room temperature for 18 hours. The reaction was quenched by pouring onto crushed ice and basifying the mixture to pH 8 with sodium hydrogen carbonate. The mixture was extracted with dichloromethane. The aqueous layer was extracted further with ethyl acetate. The organics were combined and dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The crude residue was purified by silica gel column chromatography (0%-4% methanol in dichloromethane gradient elution) to afford the title compound (16.5 g, 80%)

1. customThe reaction was quenched
2. additionby pouring
3. customonto crushed ice and basifying the mixture to pH 8 with sodium hydrogen carbonate
4. extractionThe mixture was extracted with dichloromethane
5. extractionThe aqueous layer was extracted further with ethyl acetate
6. dry with materialdried over anhydrous sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe crude residue was purified by silica gel column chromatography (0%-4% methanol in dichloromethane gradient elution)