反应详情

To a solution of 3-amino-2-methylpyridine (1.0 g, 9.25 mmol) in CHCl3 (24 ml) at 0° C. was slowly added acetic anhydride (2.0 ml, 21.3 mmol). The reaction mixture was warmed to room temperature and stirred for 1 h. Potassium acetate (272 mg, 2.77 mmol) was added followed by slow addition of isoamyl nitrite (2.7 ml, 19.9 mmol). The reaction mixture was heated at reflux overnight. The reaction mixture was cooled to room temperature and concentrated. The residue was dissolved in EtOAc and washed with water, sat'd NaHCO3 and brine then dried over MgSO4 and concentrated. The residue was purified by silica gel chromatography with 20% to 100% EtOAc/heptane to give 973 mg (65%) of 1-pyrazolo[4,3-b]pyridin-1-yl-ethanone as a light yellow solid.

1. customat 0° C.
2. temperatureThe reaction mixture was heated
3. temperatureat reflux overnight
4. temperatureThe reaction mixture was cooled to room temperature
5. concentrationconcentrated
6. dissolutionThe residue was dissolved in EtOAc
7. washwashed with water
8. dry with materialthen dried over MgSO4
9. concentrationconcentrated
10. customThe residue was purified by silica gel chromatography with 20% to 100% EtOAc/heptane