1H-pyrazole-3-carbaldehyde → HCID 178487281, compound

Participants

Reaction Steps

A mixture of 2-(4-{[2-amino-4-(methyloxy)phenyl]amino}phenyl)ethanol (step 2 of Example 71, 1.95 g, 7.56 mmol), pyrazol-3-carbaldehyde (726 mg, 7.56 mmol) in ethanol (45 ml) was heated at reflux temperature for 2 h. After cooling, the mixture was concentrated. A mixture of the residue, lead tetraacetate (4.61 g, 8.32 mmol) in benzene (50 ml) was stirred at room temperature for 16 h. The mixture was quenched with saturated NaHCO3 aqueous solution (150 ml). The whole was extracted with ethyl acetate (150 ml×4). The organic layer was washed with water (100 ml×5), brine (50 ml), dried (MgSO4), and concentrated. Purification by flash column chromatography eluting with dichloromethane/methanol (gradient elution from 20:1 to 10:1) to afford 408 mg (16%) of the title compound as an amber solid.

Provenance & Evidence