Sodium hydride → 3-Oxo-2-(3-trifluoromethyl-pyrazol-1-yl)-butyric acid benzyl ester

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Reaction Steps

To a stirring solution of 3-trifluoromethylpyrazole (0.703 g, 5.16 mmol) in THF (36.9 ml) is added NaH (0.199 g, 4.98 mmol). The reaction mixture is stirred at RT for 10 mins and then treated with 2-bromo-3-oxo-butyric acid benzyl ester (1.0 g, 3.69 mmol). After stirring at 40° C. for 30 mins, the mixture is diluted with water (50 ml) and extracted with EtOAc (2×50 ml). The combined organics are washed with brine, dried over MgSO4 and concentrated in vacuo. The crude product is purified by ISCO combiflash chromatography, eluting with 0 to 100% (iso-hexane/EtOAc) on a 24 g SiO2-column to afford the title compound; MS: m/z 327.22 [M+H]+

Provenance & Evidence