反应详情

温度

40 °C

A flask was charged with 6-chloro-1H-pyrazolo[4,3-c]pyridine (3 g, 19.54 mmol), iodine (13.11 g, 51.7 mmol), KOH (3.29 g, 58.6 mmol) and DMF (60 mL) (Note: heat generated during adding DMF). The mixture was heated at 40° C. for 16 h and then additional iodine (7.8 g, 30.7 mmol) and KOH (1.6 g, 28.4 mmol) were added. The mixture was heated at 70° C. for 3 h and then quenched with 1N Na2S2O3 and extracted with EtOAc. The organic phase was washed with water, brine and dried (Na2SO4). After evaporation of volatiles DCM was added. A solid precipitated and filtrated off to yield 6-chloro-3-iodo-1H-pyrazolo[4,3-c]pyridine (3.2 g, 11.51 mmol, 59%), which was carried out in the next step without further purification. MS ESI calc'd. for C6H4ClIN3 [M+1]+ 280, found 280.

1. temperatureThe mixture was heated at 70° C. for 3 h
2. customquenched with 1N Na2S2O3
3. extractionextracted with EtOAc
4. washThe organic phase was washed with water, brine
5. dry with materialdried (Na2SO4)
6. customAfter evaporation of volatiles DCM
7. additionwas added
8. customA solid precipitated
9. filtrationfiltrated off