5-Fluoro-3-iodo-1H-indazole synthesis

Yield:858629-06-8 96.1%

Reaction Conditions:

with iodine;potassium hydroxide in N,N-dimethyl-formamide at 20; for 0.5 h;

Steps:

616.1 Step 1

To a solution of 5-fluoro-1H-indazole (2.0 g, 14.0 mmol) in DIVIF (50 mL) was added ‘2 (7.46 g, 28.0 mmol) and KOH (2.4 g, 42 mmol), the mixture was stirred at room temperature for 0.5 hr. The reaction was monitored by TLC. After completion, the mixture was filtered, the filtrate was concentrated in vacuum to give a residue, which was purified by a silica gel column (PE/EA = 3/1) to afford 5-fluoro-3-iodo-1H-indazole (3.7 g, yield: 96.1%) as a white solid. ‘H NIVIR (400 IVIHz, DMSO-d6): ? = 13.64 (s, 1H), 7.63 (dd, J= 4.8, 4.4 Hz, 1H), 7.38-7.30 (m, 1H), 7.20 (dd, J=6.4,2.4Hz, 1H).

References:

WO2018/132372,2018,A1 Location in patent:Paragraph 01229