Malononitrile → HCID 49763815, compound

Participants

Reaction Steps

To a stirred solution of malononitrile (0.40 g, 6.1 mmol) in dimethylformamide (DMF) (5 mL) was added potassium carbonate (1.68 g, 12.2 mmol, 2 eq.). The mixture was stirred at room temperature for 15 minutes, and 4-ethoxyphenyl isothiocyanate (1.07 g, 6.1 mmol) was added. After stirring for an additional 30 minutes, 2-bromo-2′,4′-dimethoxy-acetophenone (1.57 g, 6.1 mmol, 1 eq.) was added, and the mixture stirred at room temperature overnight. The solvent was removed under reduced pressure, and water (20 mL) was added to the residue. The resulting solid was collected by filtration and dried under vacuum to give 2.80 g of crude product as a yellow solid. This crude product was combined with two similar batches (altogether totaling 7.7 g of crude product) and purified by silica gel column chromatography, eluting with hexane/ethyl acetate (2:1 then 1:1) to give 4-amino-5-(2,4-dimethoxybenzoyl)-2-[(4-ethoxyphenyl)amino]thiophene-3-carbonitrile (2.2 g) as a yellow-brown solid. 1H NMR (DMSO-d6): δ 10.24 (1H, s), 7.79 (2H, br.s), 7.21 (2H, d, J=8.6 Hz), 7.09 (1H, d, J=8.6 Hz), 6.91 (2H, d, J=9.0 Hz), 6.56 (1H, d, J=2.0 Hz), 6.49 (1H, dd, J=8.4 Hz, J=2.2 Hz), 4.02-3.96 (2H, q, J=7.0 Hz), 3.76 (3H, s), 1.92-1.57 (3H, t, J=7.0 Hz).

Provenance & Evidence