Potassium Carbonate → 2-(2-fluorophenyl)-5-[(4-iodophenyl)methyl]-2,5-dihydro-3H-pyrazolo[4,3-c]cinnolin-3-one

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Reaction Steps

1,3-Bis(2-fluorophenyl)-1H-pyrazole-4,5-dione 4-{[(4-iodophenyl)methyl]hydrazone} (50 mg, 0.097 mmol) was dissolved in degassed dimethylsulfoxide (3.5 mL), treated with potassium carbonate (120 mg, 0.87 mmol, 9.0 equiv) and placed into an oil bath preheated to 120° C. for 15 minutes. The mixture was cooled to ambient temperature, poured into sodium bicarbonate (50 mL, aqueous saturated) and extracted with ethyl acetate (2×75 mL). The combined organic extracts were dried with sodium sulfate, filtered and concentrated in vacuo. The residue was purified by silica gel gradient chromatography (100:0 to 20:80; hexanes:ethyl acetate), providing the titled compound as a dark red solid: 1H-NMR (400 MHz, CDCl3) δ 8.32 (1H, d, J=7.7 Hz), 7.70 (2H, d, J=8.3 Hz), 7.66-7.62 (1H, m), 7.59-7.55 (2H, m), 7.49 (1H, d, J=8.9 Hz), 7.42-7.36 (1H, m), 7.31-7.25 (2H, m), 7.07 (2H, d, J=8.0 Hz), 5.77 (2H, s) ppm; high resolution mass spectrometry (ES+) m/z 497.0278 [(M+H)+; calculated for C22H15FIN4O: 497.0269].

Provenance & Evidence