反应详情

5-Amino-4-(1,3-benzodioxol-5-yl)-1-methyl-1H-pyrazol-3-ol (Preparation 34) (11.39 g) was dissolved in dimethylformamide (40 ml), cesium carbonate (15.9 g) was added followed by 2-bromoethylacetate (8.16 g). The mixture was stirred at room temperature for 16 hours. The mixture was treated with water (750 ml) and extracted with ethyl acetate (2×250 ml). The organic fractions were combined washed with water (3×350 ml), brine (250 ml), dried over magnesium sulfate, filtered and evaporated. The crude product was purified on silica (300 g) eluting with ethyl acetate:hexane (3:1) to yield the title compound as a white solid (5.57 g).

1. extractionextracted with ethyl acetate (2×250 ml)
2. washThe organic fractions were combined washed with water (3×350 ml), brine (250 ml)
3. dry with materialdried over magnesium sulfate
4. filtrationfiltered
5. customevaporated
6. customThe crude product was purified on silica (300 g)
7. washeluting with ethyl acetate:hexane (3:1)