反応 #42514

反応方程式

6-aminonicotinic acid

hexanal

→

3-butylimidazo[1,2-a]pyridine-6-carboxylic acid

収率 11.9%

溶媒

isopropyl alcohol water

反応条件

後処理

1. 1
   温度cooled
2. 2
   その他The solids were removed by filtration
3. 3
   温度heated
4. 4
   温度at reflux 32 h
5. 5
   温度After cooling
6. 6
   その他the solvents were removed under reduced pressure and MeOH
7. 7
   workup.ADDITIONwas added to the residue
8. 8
   その他The resulting solid was removed by filtration
9. 9
   濃縮the filtrate was concentrated to dryness
10. 10
    workup.ADDITIONMeOH was again added
11. 11
    その他the resulting solid removed by filtration
12. 12
    その他After concentration of the filtrate, the residue was chromatographed on silica gel

実験手順

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.

出典