Malononitrile → 6-Amino-4-(4-methoxyphenyl)-1-methyl-3-phenyl-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile

Participants

Reaction Steps

A mixture of anisaldehyde (350 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-methyl-3-phenyl-1H-pyrazol-5(4H)-one (500 mg, 2.87 mmol, 1 equ.). The reaction mixture was concentrated after 24 h and the precipitate was washed with ethanol and hexanes, and product re-crystallized from ethanol to give 6-amino-4-(4-methoxyphenyl)-1-methyl-3-phenyl-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile (210 mg, 20%, 0.586 mmol) as a white solid. 1H-NMR (400 MHz) DMSO: 7.50-7.48 (d, 2H), 7.21-7.17 (m, 3H), 7.05-7.02 (m, 4H), 6.76-6.74 (d, 2H), 4.91 (s, 1H), 3.76 (s, 3H), 3.64 (s, 3H), 13C-NMR (100 MHz) DMSO: 158.9, 158.3, 146.0, 144.6, 136.9, 133.2, 128.9, 128.5, 127.8, 126.4, 120.6, 114.1, 95.9, 60.3, 55.3, 37.5, 34.5; LC/MS-MS: 359.2→293.0 m/z; GS1 and GS2 at 30, DP=66, CE=29, CXP=20, tR=3.98 min.

Provenance & Evidence