1374258-63-5

617706-18-0

1374258-63-5

The general procedure for the synthesis of 6-bromo-3-(trifluoromethyl)-1H-indazole using 1-(4-bromo-2-fluorophenyl)-2,2,2-trifluoroethanone as starting material was as follows: to a solution of 1-(4-bromo-2-fluorophenyl)-2,2,2-trifluoroethanone (1.00 g, 3.69 mmol) in 1-butanol (15 mL) was added hydrazine hydrate (3.5 mL of 45 mmol). The reaction mixture was heated to reflux and kept for 5 hours. Upon completion of the reaction, it was cooled to room temperature and stirring was continued overnight. Subsequently, the reaction mixture was diluted with distilled water (50 mL) and extracted with ethyl acetate (3 x 50 mL). The organic phases were combined, washed with saturated saline, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by fast column chromatography (eluent: 0-50% ethyl acetate/heptane gradient elution) to afford the target compound 6-bromo-3-(trifluoromethyl)-1H-indazole (310 mg, 32% yield) as an off-white solid.1H NMR (400 MHz, CDCl3, δ): 7.42 (dd, J = 8.58,1.56 Hz, 1H). 7.72 (d, J = 8.58Hz, 1H), 7.75 (dd, J = 1.56,0.78Hz, 1H).