反应详情

温度

100 °C

To a stirred solution of methylamine (0.63 mL, 33% EtOH solution, 5 mmol) in a mixture of ethanol (25 mL) and acetic acid (0.5 mL) at room temperature was added ethyl 3-oxo-3-(2-(trifluoromethyl)pyridin-3-yl)propanoate (1.305 g, 5 mmol). The reaction mixture was heated at reflux for two hours whereupon the solvent was removed by evaporation under vacuum. To a solution of the crude product in dimethylformamide (25 mL) was added potassium carbonate (2.07 g, 15 mmol) in one portion followed by 1-(3,4-bis-benzyloxy-5-nitrophenyl)-2-bromo-ethanone (2.51 g, 5.50 mmol) and the mixture was then stirred at 100° C. Once no starting material was detectable, the reaction mixture was allowed to cool to room temperature and poured onto ice-cold 1 N aqueous hydrochloric acid (100 mL). The resulting precipitate was filtered off, washed with water and dried. The residue was chromatographed over silica gel. Homogeneous fractions were pooled and evaporated to give ethyl 5-(3,4-bis(benzyloxy)-5-nitrophenyl)-1-methyl-2-(2-(trifluoromethyl)pyridin-3-yl)-1H-pyrrole-3-carboxylate, 2.492 g (79%).

1. temperatureThe reaction mixture was heated
2. temperatureat reflux for two hours whereupon the solvent
3. customwas removed by evaporation under vacuum
4. temperatureto cool to room temperature
5. additionpoured onto ice-cold 1 N aqueous hydrochloric acid (100 mL)
6. filtrationThe resulting precipitate was filtered off
7. washwashed with water
8. customdried
9. customThe residue was chromatographed over silica gel
10. customevaporated