反应详情

温度

0 °C

10 g (65.75 mmol) of 5-fluoro-1H-pyrazolo[3,4-b]pyridine-3-amine were initially charged in THF (329 ml), and the mixture was cooled to 0° C. 16.65 ml (131.46 mmol) of boron trifluoride diethyl ether complex were then added gradually. The reaction mixture was cooled further to −10° C. A solution of 10.01 g (85.45 mmol) of isopentyl nitrite in THF (24.39 ml) was then added gradually, and the mixture was stirred for a further 30 min. The mixture was diluted with cold diethyl ether (329 ml) and the resulting solid was filtered off. The diazonium salt thus prepared was added in portions to a solution at 0° C. of 12.81 g (85.45 mmol) of sodium iodide in acetone (329 ml), and the mixture was stirred at RT for 30 min. The reaction mixture was poured onto ice-water (1.8 l) and extracted twice with ethyl acetate (487 ml each time). The collected organic phases were washed with saturated aqueous sodium chloride solution (244 ml), dried, filtered and concentrated. This gave 12.1 g (86% purity, 60% of theory) of the title compound in the form of a brown solid. The crude product was converted without further purification.

1. addition16.65 ml (131.46 mmol) of boron trifluoride diethyl ether complex were then added gradually
2. temperatureThe reaction mixture was cooled further to −10° C
3. filtrationthe resulting solid was filtered off
4. customThe diazonium salt thus prepared
5. stirringthe mixture was stirred at RT for 30 min
6. additionThe reaction mixture was poured onto ice-water (1.8 l)
7. extractionextracted twice with ethyl acetate (487 ml each time)
8. washThe collected organic phases were washed with saturated aqueous sodium chloride solution (244 ml)
9. customdried
10. filtrationfiltered
11. concentrationconcentrated
12. customThe crude product was converted without further purification