反应详情

温度

100 °C

To a suspension of m-nitroaniline (2.0 g), phosphoric acid (1.67 ml), butane-2,3-dione (1.27 ml) and an aqueous solution of formaldehyde (35% w/w, 1.24 ml) in water (15 ml) was added an aqueous solution of ammonium chloride (5M, 6 ml) dropwise at 100° C. After stirring for 2 hours at 100° C., the mixture was poured into an aqueous saturated sodium hydrogen carbonate solution. The mixture was extracted with ethyl acetate. The separated organic layer was washed with water and brine, dried over magnesium sulfate and evaporated under reduced pressure. The residue was purified with a silica gel column chromatography eluting with 0-3% methanol/dichloromethane to give 4,5-dimethyl-1-(3-nitrophenyl)imidazole (135 mg, 4.3%).

1. extractionThe mixture was extracted with ethyl acetate
2. washThe separated organic layer was washed with water and brine
3. dry with materialdried over magnesium sulfate
4. customevaporated under reduced pressure
5. customThe residue was purified with a silica gel column chromatography
6. washeluting with 0-3% methanol/dichloromethane