反应详情

To a stirring solution of 1-tert-butyl-3-cyclobutyl-1,7-dihydro-pyrazolo[3,4-b]pyridin-6-one (1.0 g, 4.1 mmol) in AcOH (10 mL) was added bromine (236 uL, 4.6 mmol) dropwise. After 15 min, the resulting solid was collected and washed with hexanes. The solution was diluted with EtOAc and washed with a saturated aqueous solution of NaHCO3. The organic layer was dried over MgSO4 and concentrated under reduced pressure. Purification of the resulting material was accomplished by flash chromatography, using a Biotage® column, eluting with a gradient of 10%, 20% EtOAc/hexanes. The product-containing fractions were collected and concentrated to give the title compound (220 mg, 16% yield) as a tan solid. LRMS m/z (APCl) 322, 324 (M−1); 500 MHz 1H NMR (CDCl3) δ 12.5 (bs, 1H), 8.09 (s, 1H), 3.66 (dddd, J=8.7, 8.7, 8.7, 8.7 Hz, 1H), 2.45-2.34 (m, 4H), 2.15-1.92 (m, 2H), 1.76 (s, 9H).

1. customthe resulting solid was collected
2. washwashed with hexanes
3. additionThe solution was diluted with EtOAc
4. washwashed with a saturated aqueous solution of NaHCO3
5. dry with materialThe organic layer was dried over MgSO4
6. concentrationconcentrated under reduced pressure
7. customPurification of the resulting material
8. washeluting with a gradient of 10%, 20% EtOAc/hexanes
9. customThe product-containing fractions were collected
10. concentrationconcentrated