Yield:404827-60-7 99.4%

Reaction Conditions:

with hydrazine hydrate in butan-1-ol at 150; for 10 h;Inert atmosphere;

Steps:

10.1 Step 1: 7-fluoro-1H-indazol-3-amine

2,3-difluorobenzonitrile (10.0 g, 71.9 mmol) was dissolved in n-butanol (200 mL),then hydrazine hydrate (70.0 mL, 1440 mmol) was added dropwise under nitrogen protection.After the addition, the mixture was heated to 150 oc and refluxed for 10 hours. The reactionmixture was cooled to room temperature, and extracted with ethyl acetate (200 mL x 3). Thecombined organic layers were washed with water (200 mL x 3) and saturated brine (100 mL x 2),dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated in vacuo to givethe title compound as a yellow solid (10.8 g, 99.4%).MS (ESI, pos.ion) m/z: 152.1 (M+ 1).

References:

WO2018/188590,2018,A1 Location in patent:Paragraph 00333