To a chilled (−78° C.) stirred solution of 1.5 g (5.0 mmol) of 5-bromo-1-(4-fluorophenyl)-1H-indazole in THF was added 2.0 mL (5.0 mmol) of n-butyllithium dropwise followed by 1.0 g (4.6 mmol) of 2-chloro-5-trifluoroacetylthiophene in one portion. After 30 minutes, the mixture was diluted with 10 mL of water, warmed to room temperature and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate, and concentrated in vacuo. The residue was purified by flash chromatography using ethyl acetate-hexanes (gradient 10-30%) to afford 300 mg (15.5%) of the title compound. MS m/z 427.82 (MH+).
