Hydrochloric Acid → 6-Bromo-1H-indazole-3-carboxylic acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

The solution of 6-bromoisatin (10 g, 22 mmol) in 1N aqueous NaOH solution (48 Ml) was stirred at 50° C. for 1 h. The mixture was cooled to 0° C. Sodium nitrite (3 g, 22 mmol) solution in water (11 Ml) was added dropwise for 15 min at 0° C. The mixture was added to the solution of water (90 Ml) and sulfuric acid (4.6 Ml) at 0° C. for 15 min. The mixture was added to the solution of conc. hydrochloric acid (40 Ml) and SnCl2.2H2O (24 g, 53 mmol). After 1 h, the mixture was filtered and washed with water. The solid was dried through air flow to give the titled compound (8.98 g).

Herkunft & Nachweise