反应详情

To a solution of 6-methyl-1H-pyrazolo[3,4-b]pyridine (4.44 g) and iodine (16.9 g) in N,N-dimethylformamide (100 mL) was added potassium hydroxide (7.48 g) under ice-cooling, and the mixture was stirred at room temperature for 4 hours. The reaction solution was poured into ice water, and the precipitate was filtered. The filtrate was extracted with ethyl acetate, washed with saturated saline, and then dried over sodium sulfate and concentrated under reduced pressure. The resulting residue was combined with the above-mentioned precipitate and purified by silica gel column chromatography (eluent: chloroform→chloroform/methanol=19/1) to give 3-iodo-6-methyl-1H-pyrazolo[3,4-b]pyridine [REx(104-2)] (6.48 g) as a brown powder.

1. temperaturecooling
2. filtrationthe precipitate was filtered
3. extractionThe filtrate was extracted with ethyl acetate
4. washwashed with saturated saline
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated under reduced pressure
7. custompurified by silica gel column chromatography (eluent: chloroform→chloroform/methanol=19/1)