Hydrochloric Acid → HCID 86597534, compound

Participants

Reaction Conditions

Reaction Steps

Alternatively, lithium bis(trimethylsilyl)amide (1.0M solution in THF, 1.1 mL, 1.1 mmol) was slowly added to a solution of 1-[1-(3-trifluoromethyl-pyridin-2-yl)-1H-pyrazol-4-yl]-ethanone (240 mg, 0.94 mmol) in 2 mL anhydrous THF at −78° C. under nitrogen. The mixture was then allowed to warm to −20° C. and kept at −20° C. to −5° C. for 3 hrs. After this period of time the mixture was cooled to −78° C. and to it was added ethyl trifluoroacetate (200 mg, 0.41 mmol). The mixture was next allowed to warm to ambient temperature overnight. 1N aqueous HCl was carefully added to adjust the pH 2. Two layers were separated and the aqueous layer was extracted with chloroform three times. The extract was washed with brine, dried over sodium sulfate, and concentrated in vacuo to give 4,4,4-trifluoro-1-[1-(3-trifluoromethyl-pyridin-2-yl)-1H-pyrazol-4-yl]-butane-1,3-dione as a yellow solid (290 mg, 88% yield). The product was used for the next step without purification. 1H-NMR (400 MHz, CDCl3): δ 6.35 (s, 1H), 7.59 (dd, 1H, J=4.80, J=7.83), 8.21 (s, 1H), 8.28 (dd, 1H, J=1.77, J=3.80), 8.75 (dd, 1H, J=4.80, J=1.77), 8.76 (d, 1H, J=0.51)

Provenance & Evidence