Hydrazine → HCID 178437989, compound

Participants

Reaction Conditions

Reaction Steps

To 1-(5-bromo-2-fluorophenyl)propan-1-one (10 g, 43 mmol), anhydrous hydrazine (53 mL) was added and heated at reflux (70-75° C.) for 2 days. Excess hydrazine was distilled out under vacuum from the reaction mixture. To this was added xylene (60 mL) and the mixture heated to 145-150° C. for 3 days. Xylene was concentrated completely under vacuum to give a crude product, which was purified by column chromatography using 8% ethyl acetate/pet-ether as eluents to afford 5-bromo-3-ethyl-1H-indazole (4 g, 40%) as a solid. 1H NMR (CDCl3): δ 9.6-10.0 (br, 1H), 7.9 (s, 1H), 7.5 (d, 1H), 7.3 (d, 1H), 3.0 (q, 2H), 1.4 (t, 3H).

Provenance & Evidence