Lithium diisopropylamide → 1-Allyl-4-bromo-5-{2,2,2-trifluoro-1-[1-(4-fluorophenyl)-1H-indazol-5-yl]-1-hydroxyethyl}-1H-pyrazole-3-carbonitrile

Participants

Reaction Steps

To a chilled (−78° C.) solution of 1-allyl-4-bromo-1H-pyrazole-3-carbonitrile (116 mg, 0.550 mmol) in dry THF (2 mL) was added lithium diisopropylamide (367 μL, 1.5 M solution in hexanes, 0.55 mmol). After 5 minutes, a chilled (−78° C.) solution of 2,2,2-trifluoro-1-[1-(4-fluorophenyl)-1H-indazol-5-yl]ethanone (154 mg, 0.500 mmol) in 2 mL of THF was added. After 15 minutes, the mixture was warmed to room temperature, quenched with 10 mL of saturated aqueous sodium bicarbonate and extracted with three 10 mL portions of ethyl ether. The combined organic layers were washed with 10 mL of brine, dried over sodium sulfate, filtered, and concentrated in vacuo. The residue was chromatographed on SiO2 (0-50% ethyl acetate in hexanes, gradient) to afford 213 mg (82%) of the title product. MS m/z 520.19/522.20 (M+).

Provenance & Evidence