Bromine → 5-bromo-6-fluoro-1H-indazole-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 6-fluoro-1H-indazole-3-carboxylic acid (4.95 g, 23.8 mmol) and acetic acid (50 mL) was treated with bromine (2.0 mL, 38 mmol) dropwise at room temperature. The reaction mixture was heated to 90° C. and stirred for 16 hours under an atmosphere of nitrogen. The reaction mixture was then exposed to the atmosphere and stirred at 95° C. for 72 hours. The resulting solids were collected while the reaction mixture was still hot and rinsed with diethyl ether two times. The solids were dried at 50° C. under reduced pressure to give the title compound (2.89 g). 1H NMR (500 MHz, DMSO-d6) δ 8.31 (d, J=6.8 Hz, 1H), 7.71 (d, J=8.8 Hz, 1H).

Provenance & Evidence