2,3,4,5-Tetrafluoronitrobenzene → 5-cyclopropyl-N-(2,3,4-trifluoro-6-nitrophenyl)-1H-pyrazol-3-amine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To 1,2,3,4-tetrafluoro-5-nitrobenzene (3.0 g, 15.4 mmol) and DIEA (3.7 ml, 21.0 mmol) in dry THF (20 ml) was added 5-cyclopropyl-1H-pyrazol-3-amine (1.7 g, 14.0 mmol) in THF (5 ml) drop wise at 0° C. After addition, the reaction mixture was stirred at 25° C. for 16 hours. The solvent was removed under reduced pressure and the resulted residue was purified by column chromatography (hexane-EtOAc=4:1). This was recrystallized from Et2O (20 ml) and hexanes (˜150 ml) to give the title compound as red crystals (0.650 g, 16%). 1H NMR (400 MHz) 11.84 (s, 1H), 8.67 (s, 1H), 8.06 (m, 1H), 5.57 (s, 1H), 1.82 (m, 1H), 0.89 (m, 2H), 0.65 (m, 2H). MS: Calcd.: 298; Found: [M+H]+ 299.

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