Trifluoroacetic acid → 1-[[5-(4-fluorophenyl)-4-(4-pyridinyl)-1H-pyrazol-3-yl]carbonyl]piperazine, monohydrate

Participants

Reaction Steps

A solution of 1,1-dimethylethyl 4-[[5-(4-fluorophenyl)-4-(4-pyridinyl)-1H-pyrazol-3-yl]carbonyl]-1-piperazinecarboxylate (0.6349 g; 1.4077 mmol; prepared as set forth in step 2 of Example A-313) in methylene chloride (3.5 mL) and TFA (1.1 mL, 14.077 mmol) was stirred at room temperature under N2 for 2 hours. The solvents were removed under reduced pressure, and TFA was chased by methylene chloride and methanol. The resulting colorless oily residue was triturated with methanol. The resulting solid was collected by filtration and dried in a vacuum oven overnight to give the desired product 1-[[5-(4-fluorophenyl)-4-(4-pyridinyl)-1H-pyrazol-3-yl]carbonyl]piperazine, monohydrate (0.7860 g, 96.4%). Anal. Calc'd for C19H18N5F.2TFA.H2O: C, 46.24; H, 3.71; N, 11.72; Found: C, 45.87; H, 3.43; N, 11.45. MS (MH+): 352 (base peak).

Provenance & Evidence