反应详情

To a solution of 13.67 g (61.56 mmol) of 3-bromo-1H-indazole-5-carbonitrile and 2.06 g (10.8 mmol, 0.175 equiv.) of p-toluenesulfonic acid monohydrate in 247 mL of anhydrous tetrahydrofuran (THF) was added 11.2 mL (123 mmol, 2.00 equiv.) of 3,4-dihydro-2H-pyran. The mixture was refluxed under a nitrogen atmosphere for 14 h. The reaction was quenched with saturated aqueous sodium bicarbonate (sat. aq. NaHCO3). The mixture was extracted twice with EtOAc. The combined organics were washed with 2×sat. aq. NaHCO3, 1×sat. aq. NaCl, and dried over Na2SO4. Chromatography of the crude material on 200 g of silica gel using 30% EtOAc in hexanes afforded the title compound (14.34 g, 76% yield): ES-MS (m/z) 306 [M+1]+.

1. temperatureThe mixture was refluxed under a nitrogen atmosphere for 14 h
2. customThe reaction was quenched with saturated aqueous sodium bicarbonate (sat. aq. NaHCO3)
3. extractionThe mixture was extracted twice with EtOAc
4. washThe combined organics were washed with 2×
5. dry with materialaq. NaCl, and dried over Na2SO4