反应详情

温度

0 °C

To N1-(4-fluorophenyl)-5-aminoindazole (25.6 g, 113 mmol) suspended in 500 mL 6 M HCl and cooled to 0° C. was added a solution of sodium nitrite (8.2 g, 119 mmol) dissolved in 75 mL water, portionwise. After 3 h, potassium iodide (22.5 g, 136 mmol) dissolved in 80 mL water was added and the reaction was stirred overnight. The next day, the reaction was transferred to a beaker and carefully quenched by adding solid sodium carbonate. After neutralization and addition of water, the aqueous phase was extracted 4× EtOAc. The combined organic extracts were dried over MgSO4, filtered, concentrated, and filtered from hot EtOAc. The filtrate was concentrated and purified on a 330 g SiO2 MPLC column using DCM. Obtained 13.2 g of 1-(4-fluorophenyl)-5-iodo-1H-indazole (39%). MS found: (M+H)+=339.

1. additionwas added
2. customcarefully quenched
3. additionby adding solid sodium carbonate
4. additionAfter neutralization and addition of water
5. extractionthe aqueous phase was extracted 4× EtOAc
6. dry with materialThe combined organic extracts were dried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated
9. filtrationfiltered from hot EtOAc
10. concentrationThe filtrate was concentrated
11. custompurified on a 330 g SiO2 MPLC column