反应详情

温度

150 °C

5,6-Diamino-1-ethyl-3,3-dimethyl-1,3-dihydro-indol-2-one (5.00 g, 22.80 mmol), and 4-nitro-pyrazole carboxylic acid (3.58 g, 22.80 mmol) were mixed with polyphosphoric acid (22.34 g, 228.0 mmol) and phosphorus pentoxide (1.63 g, 11.4 mmol) and stirred under nitrogen at 150° C. for 6 h. It was quenched with ice water (250 ml) and the resulting suspension was adjusted to pH 5 by adding aqueous ammonia. The crude microcrystalline solid was dissolved in ethyl acetate (400 mL). The organic layer was separated and the aqueous layer was further extracted with ethyl acetate (4×400 mL). After evaporation of the solvent, the crude product was purified by HPLC (High Performance Liquid Chromatography). 5-Ethyl-7,7-dimethyl-2-(4-nitro-1H-pyrazol-3-yl)-5,7-dihydro-1H-imidazo[4,5-f]indol-6-one was obtained as an orange solid (2.47 g, 32%).

1. customIt was quenched with ice water (250 ml)
2. additionby adding aqueous ammonia
3. dissolutionThe crude microcrystalline solid was dissolved in ethyl acetate (400 mL)
4. customThe organic layer was separated
5. extractionthe aqueous layer was further extracted with ethyl acetate (4×400 mL)
6. customAfter evaporation of the solvent
7. customthe crude product was purified by HPLC (High Performance Liquid Chromatography)