2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → HCID 66693755, compound

Participants

Reaction Steps

To a stirred solution of 4-methylbenzaldehyde (723 mg, 6.02 mmol), 1H-pyrazol-5-amine (500 mg, 6.02 mmol), and methyl 3-oxobutanoate (769 mg, 6.62 mmol) in THF (80 mL) and heptane (20 mL) was added piperidine (10 mL, 0.101 mmol). The reaction mixture was heated at reflux for 20 h. The solvent was evaporated and the crude material was dissolved in CH2Cl2. DDQ (1229 mg, 5.42 mmol) was added and the mixture was stirred at room temperature for 1 h. The solvent was evaporated. Purification by silica gel chromatography provided the title compound (1120 mg, 66.2%). 1H-NMR (500 MHz, CD Cl3) δ ppm 2.44 (3H, s), 2.65 (3H, s), 3.63 (3H, s), 6.65 (1H, d, J=2.4 Hz), 7.34 (2H, d, J=8.1 Hz), 7.52 (2H, d, J=8.1 Hz), 8.10 (1H, d, J=2.4 Hz).

Provenance & Evidence