Hexanal → 3-Butylimidazo[1,2-a]pyridine-6-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To hexanal (1.02 g, 10.2 mmol) in 15 mL of isopropyl alcohol-water (4:1 v/v) was added CuCl2 (1.37 g, 10.2 mmol). The mixture was heated at 80° C. for 2.5 h, then cooled. The solids were removed by filtration and the filtrate was added to 6-aminonicotinic acid (1.35 g, 10 mmol). The mixture was stirred overnight at room temperature, then heated at reflux 32 h. After cooling, the solvents were removed under reduced pressure and MeOH was added to the residue. The resulting solid was removed by filtration and the filtrate was concentrated to dryness. MeOH was again added, and the resulting solid removed by filtration. After concentration of the filtrate, the residue was chromatographed on silica gel using MeOH-dichloromethane (33/67) to give 0.26 g of 3-butylimidazo[1,2-a]pyridine-6-carboxylic acid.

Provenance & Evidence