Malononitrile → 6-Amino-4-(4-fluorophenyl)-1,3-diphenyl-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile

Participants

Reaction Steps

A mixture of 4-fluorobenzaldehyde (300 μL, 2.87 mmol, 1.0 equ.), malononitrile (190 mg, 2.87 mmol, 1.0 equ.) and triethylamine (400 μL, 2.87 mmol, 1.0 equ.) in ethanol (10 mL) was stirred for 1 min, followed by the addition of 1,3-diphenyl-1H-pyrazol-5(4H)-one (678 mg, 2.87 mmol, 1 equ.). The precipitate formed was filtered out and washed with ethanol and hexanes, and re-crystallized from ethanol to afford 6-amino-4-(4-fluorophenyl)-1,3-diphenyl-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile (240 mg, 0.588 mmol, 20%) as a white powder. 1H-NMR (400 MHz) DMSO: 7.94-7.92 (d, 2H), 7.61-7.55 (m, 4H), 7.42-7.38 (t, 1H), 7.28-7.24 (m, 7H), 7.06-7.02 (t, 2H), 5.15 (s, 1H), 13C-NMR (100 MHz) DMSO: 162.6, 159.0, 146.8, 145.6, 140.6, 137.8, 132.5, 130.0, 129.9, 129.8, 128.6, 128.6, 127.3, 127.0, 121.3, 120.2, 115.6, 115.4, 97.9, 59.6, 37.0; LC/MS-MS: 410.4→242.2 m/z; GS1 and GS2 at 30, DP=21, CE=47, CXP=16, tR=4.63 min.

Provenance & Evidence