反应详情

To a solution of 3-methyl-5-nitro-1H-indazole (1.50 g, 8.44 mmol, commercially available) in dry DMF (30 mL) under Argon was added NaH (0.43 g, 17.79 mmol) portionwise at 0° C. After 30 min, ethyl iodide (1.98 g, 1.03 mL, 12.7 mmol) was added and the mixture stirred at ambient temperature for 1 h then quenched by the addition of H2O (2 mL), concentrated and redissolved in EtOAc (30 mL) then washed with H2O (3×15 mL). The combined aqueous layers were extracted with EtOAc (3×15 mL) and the combined organic layers dried over Na2SO4, filtered and concentrated. Purification by chromatography (SiO2, heptane:ethyl acetate=95:5 to 50:50) afforded the title compound (1.17 g, 67%) as a yellow solid. MS m/e: 206.0 [M+H]−.

1. customthen quenched by the addition of H2O (2 mL)
2. concentrationconcentrated
3. dissolutionredissolved in EtOAc (30 mL)
4. washthen washed with H2O (3×15 mL)
5. extractionThe combined aqueous layers were extracted with EtOAc (3×15 mL)
6. dry with materialthe combined organic layers dried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated
9. customPurification by chromatography (SiO2, heptane:ethyl acetate=95:5 to 50:50)