反应详情

温度

70 °C

To a mixture of 3-(3-methyl-1H-pyrazol-1-yl)pyridine (6.7 g, 42.1 mmol), iodic acid (2.96 g, 16.84 mmol), and diiodine (8.55 g, 33.7 mmol) in acetic acid (60.1 ml) was added concentrated sulfur acid (3.74 ml, 21.04 mmol). The reaction mixture heated to 70° C. for 30 minutes. The reaction mixture was poured onto ice with sodium thiosulfate and was extracted with diethyl ether. The combined organic phases were washed with saturated aqueous sodium bicarbonate. The organic phases were then dried with magnesium sulfate, filtered and concentrated in vacuo. The solid residue was dissolved in dichloromethane, applied to a 80 g silica gel column, and eluted with 0-80% acetone in hexanes to afford 3-(4-iodo-3-methyl-1H-pyrazol-1-yl)pyridine (11.3 g, 35.7 mmol, 85%) as a white solid: mp 131° C.; 1H NMR (400 MHz, CDCl3) δ 8.95-8.85 (m, 1H), 8.52 (dd, J=4.8, 1.4 Hz, 1H), 8.00-7.94 (m, 1H), 7.91 (s, 1H), 7.38 (ddd, J=8.3, 4.8, 0.7 Hz, 1H), 2.34 (s, 3H); EIMS m/z 285.

1. extractionwas extracted with diethyl ether
2. washThe combined organic phases were washed with saturated aqueous sodium bicarbonate
3. dry with materialThe organic phases were then dried with magnesium sulfate
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. dissolutionThe solid residue was dissolved in dichloromethane
7. washeluted with 0-80% acetone in hexanes