反应详情

tert-Butyl 6-chloro-3-oxo-2,3-dihydro-1H-pyrazolo[4,3-c]pyridine-1-carboxylate (1.19 g, 4.41 mmol), iodoethane (0.715 mL, 8.85 mmol), and cesium carbonate (4.36 g, 13.38 mmol) were stirred in DMF (15 mL) at room temperature for 16 h. Water was added and the products extracted into EtOAc (×2). The combined organic extracts were washed with brine, dried over Na2SO4, filtered, and concentrated in vacuo. Purification of the residue by flash chromatography (6-50% EtOAc-hexanes) gave tert-butyl 6-chloro-3-ethoxy-1H-pyrazolo[4,3-c]pyridine-1-carboxylate. MS ESI calc'd. For C13H16ClN3O3 [M+1]+ 298. found 298.

1. extractionthe products extracted into EtOAc (×2)
2. washThe combined organic extracts were washed with brine
3. dry with materialdried over Na2SO4
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customPurification of the residue by flash chromatography (6-50% EtOAc-hexanes)