反应详情

500 mg (375 mmol) of 1H-indazol-4-ylamine (prepared according to J. Chem. Soc. 1955, 2412, 2419) are stirred in 10% strength sulfuric acid at 180° C. in an autoclave at intrinsic pressure overnight. The reaction solution is cooled to room temperature and neutralized with 1N sodium hydroxide solution, and the salts are filtered off. The filtrate is concentrated to dryness.

1. filtrationthe salts are filtered off
2. concentrationThe filtrate is concentrated to dryness