反应详情

To 2-{[5-amino-1-methyl-4-(4-methylphenyl)-1H-pyrazol-3-yl]oxy}ethyl acetate (Preparation 5) (1.0 g) in dimethylacetamide (10 ml) at 0° C. under an atmosphere of nitrogen was added sodium hydride (60% dispersion in oil, 415 mg) followed by 4-tert-amylbenzenesulphonyl chloride and (938 mg), the mixture was stirred for 2 hrs. The reaction was diluted with water (50 ml) and extracted with dichloromethane (5×30 ml). The crude mixture was dissolved in ethanol (50 ml) and sodium hydroxide (2N, 5 ml) was added, the mixture was stirred at room temperature for 48 hrs and then neutralised to pH 7 by addition of hydrochloric acid (2N) and extracted with dichloromethane (2×50 ml). The organic fractions were combined, dried over magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by column chromatography (silica, 10 g) eluted with ethyl acetate:hexane (1:1) to yield the title compound as a white solid (290 mg).

1. extractionextracted with dichloromethane (5×30 ml)
2. dissolutionThe crude mixture was dissolved in ethanol (50 ml)
3. additionsodium hydroxide (2N, 5 ml) was added
4. stirringthe mixture was stirred at room temperature for 48 hrs
5. additionneutralised to pH 7 by addition of hydrochloric acid (2N)
6. extractionextracted with dichloromethane (2×50 ml)
7. dry with materialdried over magnesium sulfate
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customThe residue was purified by column chromatography (silica, 10 g)
11. washeluted with ethyl acetate:hexane (1:1)