Hydrochloric Acid → 2-(6-Chloroimidazo[1,2-b]pyridazin-2-yl)propan-2-ol

Temperature

-20 °C

A solution of 2-methyltetrahydrofuran (0.45 mL, 4.43 mmol) in toluene (6.1 mL) was cooled to −20° C. and methylmagnesium chloride (14.8 ml, 44.3 mmol) was added dropwise over five minutes. The solution was stirred for 30 minutes at −20° C., warmed to 0° C. and stirred for 15 minutes, and then re-cooled to −20° C. Ethyl 6-chloroimidazo[1,2-B]pyridazine-2-carboxylate (1 g, 4.43 mmol) was added in portions and the resulting mixture was stirred at 0° C. for 30 minutes then poured into a flask containing 40 ml of cooled (0° C.) 1 N HCl, diluted with ethyl acetate (40 mL) and stirred for ten minutes. The resulting organic layer was washed with saturated aqueous sodium bicarbonate and sodium chloride. The aqueous later was neutralized with saturated aqueous sodium bicarbonate and extracted with ethyl acetate. The organic layers were combined, dried over magnesium sulfate, filtered, concentrated, and purified via silica gel chromatography (0-15% methanol in dichloromethane) to afford the title compound as a white solid.

1. temperaturewarmed to 0° C.
2. stirringstirred for 15 minutes
3. temperaturere-cooled to −20° C
4. stirringthe resulting mixture was stirred at 0° C. for 30 minutes
5. additionthen poured into a flask
6. additioncontaining 40 ml
7. stirringstirred for ten minutes
8. washThe resulting organic layer was washed with saturated aqueous sodium bicarbonate and sodium chloride
9. extractionextracted with ethyl acetate
10. dry with materialdried over magnesium sulfate
11. filtrationfiltered
12. concentrationconcentrated
13. custompurified via silica gel chromatography (0-15% methanol in dichloromethane)

ORD record

ord-202572395b7f42a493108682db829529

Source dataset

uspto-grants-2013_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08344144B2