反应详情

A mixture of 4-[6-(cyclopropylmethoxy)imidazo[1,2-a]pyridin-2-yl]phenyl acetate (425 mg), 2,6-dichloro-1-fluoropyridinium trifluoromethanesulfonate (1.25 g) and acetonitrile (6 mL) was stirred at room temperature for 4 hr. To the reaction mixture was added saturated aqueous sodium hydrogen carbonate solution, and the mixture was extracted twice with ethyl acetate. The combined organic layer was washed with saturated brine, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate), and the obtained compound was dissolved in methanol (6 mL). 1M Aqueous sodium hydroxide solution (0.66 mL) was added at room temperature, and the mixture was stirred for 1 hr, and concentrated under reduced pressure. The residue was diluted with ethyl acetate and water, and the mixture was neutralized with 1M hydrochloric acid, and the aqueous layer was separated from the organic layer. The separated aqueous layer was extracted again with ethyl acetate. The combined organic layer was washed with saturated brine, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by basic silica gel column chromatography (hexane/ethyl acetate) to give the title compound as a pale-brown powder (54 mg).

1. extractionthe mixture was extracted twice with ethyl acetate
2. washThe combined organic layer was washed with saturated brine
3. dry with materialdried over anhydrous magnesium sulfate
4. customthe solvent was evaporated under reduced pressure
5. customThe residue was purified by silica gel column chromatography (hexane/ethyl acetate)
6. dissolutionthe obtained compound was dissolved in methanol (6 mL)
7. addition1M Aqueous sodium hydroxide solution (0.66 mL) was added at room temperature
8. stirringthe mixture was stirred for 1 hr
9. concentrationconcentrated under reduced pressure
10. additionThe residue was diluted with ethyl acetate and water
11. customthe aqueous layer was separated from the organic layer
12. extractionThe separated aqueous layer was extracted again with ethyl acetate
13. washThe combined organic layer was washed with saturated brine
14. dry with materialdried over anhydrous magnesium sulfate
15. customthe solvent was evaporated under reduced pressure
16. customThe residue was purified by basic silica gel column chromatography (hexane/ethyl acetate)